Skip ssh host tests on ci.jenkins.io (#1255)

The GitHub.com SSH abuse prevention system rejects connections from
the tests when they are run on ci.jenkins.io.  These tests should only
be run as end to end acceptance tests but they are not too disruptive
(for now) to continue to be included in the default tests.

Additional tests should be created that use test containers so that they
can use the ssh connection on the test container instead of using the
GitHub.com SSH servers.

Unfortunately, I can't prioritize that test rewrite now, so these tests
are disabled on ci.jenkins.io.

(cherry picked from commit 2d90e37)

src/test/java/org/jenkinsci/plugins/gitclient/verifier/AcceptFirstConnectionVerifierTest.java

@@ -5,6 +5,7 @@
 import static org.hamcrest.Matchers.hasItem;
 import static org.hamcrest.Matchers.is;
 import static org.hamcrest.io.FileMatchers.anExistingFile;
+import static org.jenkinsci.plugins.gitclient.verifier.KnownHostsTestUtil.runKnownHostsTests;
 import static org.mockito.Mockito.spy;
 import static org.mockito.Mockito.when;
 
@@ -17,6 +18,7 @@
 import java.util.Collections;
 import java.util.List;
 import org.awaitility.Awaitility;
+import org.junit.Assume;
 import org.junit.Ignore;
 import org.junit.Rule;
 import org.junit.Test;
@@ -46,13 +48,15 @@ public class AcceptFirstConnectionVerifierTest {
 
     @Test
     public void testVerifyHostKeyOption() throws IOException {
+        Assume.assumeTrue(runKnownHostsTests());
         assertThat(
                 new AcceptFirstConnectionVerifier().forCliGit(TaskListener.NULL).getVerifyHostKeyOption(null),
                 is("-o StrictHostKeyChecking=accept-new -o HashKnownHosts=yes"));
     }
 
     @Test
     public void testVerifyServerHostKeyWhenFirstConnection() throws Exception {
+        Assume.assumeTrue(runKnownHostsTests());
         File file = new File(testFolder.getRoot() + "path/to/file");
         AcceptFirstConnectionVerifier acceptFirstConnectionVerifier = spy(new AcceptFirstConnectionVerifier());
         when(acceptFirstConnectionVerifier.getKnownHostsFile()).thenReturn(file);
@@ -77,6 +81,7 @@ public void testVerifyServerHostKeyWhenFirstConnection() throws Exception {
 
     @Test
     public void testVerifyServerHostKeyWhenSecondConnectionWithEqualKeys() throws Exception {
+        Assume.assumeTrue(runKnownHostsTests());
         String hostKeyEntry =
                 "|1|FJGXVAi7jMQIsl1J6uE6KnCiteM=|xlH92KQ91GuBgRxvRbU/sBo60Bo= ecdsa-sha2-nistp256 AAAAE2VjZHNhLXNoYTItbmlzdHAyNTYAAAAIbmlzdHAyNTYAAABBBEmKSENjQEezOmxkZMy7opKgwFB9nkt5YRrYMjNuG5N87uRgg6CLrbo5wAdT/y6v0mKV0U2w0WZ2YB/++Tpockg=";
 
@@ -105,6 +110,7 @@ public void testVerifyServerHostKeyWhenSecondConnectionWithEqualKeys() throws Ex
 
     @Test
     public void testVerifyServerHostKeyWhenHostnameWithoutPort() throws Exception {
+        Assume.assumeTrue(runKnownHostsTests());
         String hostKeyEntry =
                 "github.com ecdsa-sha2-nistp256 AAAAE2VjZHNhLXNoYTItbmlzdHAyNTYAAAAIbmlzdHAyNTYAAABBBEmKSENjQEezOmxkZMy7opKgwFB9nkt5YRrYMjNuG5N87uRgg6CLrbo5wAdT/y6v0mKV0U2w0WZ2YB/++Tpockg=";
         File mockedKnownHosts = knownHostsTestUtil.createFakeKnownHosts(hostKeyEntry);
@@ -128,6 +134,7 @@ public void testVerifyServerHostKeyWhenHostnameWithoutPort() throws Exception {
 
     @Test
     public void testVerifyServerHostKeyWhenSecondConnectionWhenNotDefaultAlgorithm() throws Exception {
+        Assume.assumeTrue(runKnownHostsTests());
         String fileContent =
                 """
                 github.com,140.82.121.4\
@@ -158,6 +165,7 @@ public void testVerifyServerHostKeyWhenSecondConnectionWhenNotDefaultAlgorithm()
     @Test
     @Ignore("FIXME not sure what is the test here")
     public void testVerifyServerHostKeyWhenSecondConnectionWithNonEqualKeys() throws Exception {
+        Assume.assumeTrue(runKnownHostsTests());
         String fileContent =
                 """
                 |1|f7esvmtaiBk+EMHjPzWbRYRpBPY=|T7Qe4QAksYPZPwYEx5QxQykSjfc=\
@@ -188,6 +196,7 @@ public void testVerifyServerHostKeyWhenSecondConnectionWithNonEqualKeys() throws
 
     @Test
     public void testVerifyServerHostKeyWhenConnectionWithAnotherHost() throws Exception {
+        Assume.assumeTrue(runKnownHostsTests());
         String bitbucketFileContent =
                 """
                 |1|HnmPCP38pBhCY0NUtBXSraOg9pM=|L6YZ9asEeb2xplTDEThGOxRq7ZY=\
@@ -220,6 +229,7 @@ public void testVerifyServerHostKeyWhenConnectionWithAnotherHost() throws Except
 
     @Test
     public void testVerifyServerHostKeyWhenHostnamePortProvided() throws Exception {
+        Assume.assumeTrue(runKnownHostsTests());
         String fileContent =
                 """
                 |1|6uMj3M7sLgZpn54vQbGqgPNTCVM=|OkV9Lu9REJZR5QCVrITAIY34I1M=\

src/test/java/org/jenkinsci/plugins/gitclient/verifier/KnownHostsFileVerifierTest.java

@@ -64,6 +64,7 @@ public void connectWhenHostKeyNotInKnownHostsFileForOtherHostNameThenShouldFail(
 
     @Test
     public void connectWhenHostKeyProvidedThenShouldNotFail() throws IOException {
+        Assume.assumeTrue(runKnownHostsTests());
         KnownHostsFileVerifier knownHostsFileVerifier = spy(new KnownHostsFileVerifier());
         when(knownHostsFileVerifier.getKnownHostsFile()).thenReturn(fakeKnownHosts);
 
@@ -84,6 +85,7 @@ public void connectWhenHostKeyProvidedThenShouldNotFail() throws IOException {
 
     @Test
     public void connectWhenHostKeyInKnownHostsFileWithNotDefaultAlgorithmThenShouldNotFail() throws IOException {
+        Assume.assumeTrue(runKnownHostsTests());
         fakeKnownHosts = knownHostsTestUtil.createFakeKnownHosts(
                 "fake2.ssh",
                 "known_hosts_fake2",

src/test/java/org/jenkinsci/plugins/gitclient/verifier/ManuallyProvidedKeyVerifierTest.java

@@ -60,6 +60,7 @@ public void connectWhenHostKeyProvidedForOtherHostNameThenShouldFail() throws Ex
 
     @Test
     public void connectWhenHostKeyProvidedThenShouldNotFail() throws Exception {
+        Assume.assumeTrue(runKnownHostsTests());
         ManuallyProvidedKeyVerifier verifier = new ManuallyProvidedKeyVerifier(hostKey);
         ManuallyProvidedKeyVerifier.ManuallyProvidedKeyJGitHostKeyVerifier jGitHostKeyVerifier =
                 (ManuallyProvidedKeyVerifier.ManuallyProvidedKeyJGitHostKeyVerifier)
@@ -78,6 +79,7 @@ public void connectWhenHostKeyProvidedThenShouldNotFail() throws Exception {
 
     @Test
     public void connectWhenWrongHostKeyProvidedThenShouldFail() throws Exception {
+        Assume.assumeTrue(runKnownHostsTests());
         String key = "github.com ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIOMqqnkVzrm0SdG6UOoqKLsabgH5C9okWi0dh2l9OOOO";
         HostKeyVerifierFactory verifier = new ManuallyProvidedKeyVerifier(key);
 
@@ -97,6 +99,7 @@ public void connectWhenWrongHostKeyProvidedThenShouldFail() throws Exception {
 
     @Test
     public void connectWhenHostKeyProvidedWithPortThenShouldNotFail() throws Exception {
+        Assume.assumeTrue(runKnownHostsTests());
         String key =
                 "github.com:22 ecdsa-sha2-nistp256 AAAAE2VjZHNhLXNoYTItbmlzdHAyNTYAAAAIbmlzdHAyNTYAAABBBEmKSENjQEezOmxkZMy7opKgwFB9nkt5YRrYMjNuG5N87uRgg6CLrbo5wAdT/y6v0mKV0U2w0WZ2YB/++Tpockg=";
         HostKeyVerifierFactory verifier = new ManuallyProvidedKeyVerifier(key);

src/test/java/org/jenkinsci/plugins/gitclient/verifier/NoHostKeyVerifierTest.java

@@ -2,13 +2,15 @@
 
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.is;
+import static org.jenkinsci.plugins.gitclient.verifier.KnownHostsTestUtil.runKnownHostsTests;
 
 import hudson.model.StreamBuildListener;
 import hudson.model.TaskListener;
 import java.io.IOException;
 import java.nio.file.Path;
 import java.time.Duration;
 import org.awaitility.Awaitility;
+import org.junit.Assume;
 import org.junit.Before;
 import org.junit.Test;
 
@@ -23,6 +25,7 @@ public void assignVerifier() {
 
     @Test
     public void verifyServerHostKey() throws IOException {
+        Assume.assumeTrue(runKnownHostsTests());
         NoHostKeyVerifier acceptFirstConnectionVerifier = new NoHostKeyVerifier();
 
         KnownHostsTestUtil.connectToHost(