Remove deprecated 'reindex.remote.whitelist` setting (#17188)

This has been replaced by `reindex.remote.allowlist`.

Signed-off-by: Andrew Ross <andrross@amazon.com>

Author: andrross

modules/reindex/src/main/java/org/opensearch/index/reindex/ReindexModulePlugin.java

@@ -130,7 +130,6 @@ public Collection<Object> createComponents(
     @Override
     public List<Setting<?>> getSettings() {
         final List<Setting<?>> settings = new ArrayList<>();
-        settings.add(TransportReindexAction.REMOTE_CLUSTER_WHITELIST);
         settings.add(TransportReindexAction.REMOTE_CLUSTER_ALLOWLIST);
         settings.add(TransportReindexAction.REMOTE_REINDEX_RETRY_INITIAL_BACKOFF);
         settings.add(TransportReindexAction.REMOTE_REINDEX_RETRY_MAX_COUNT);

modules/reindex/src/main/java/org/opensearch/index/reindex/TransportReindexAction.java

@@ -57,18 +57,9 @@
 import static java.util.Collections.emptyList;
 
 public class TransportReindexAction extends HandledTransportAction<ReindexRequest, BulkByScrollResponse> {
-    static final Setting<List<String>> REMOTE_CLUSTER_WHITELIST = Setting.listSetting(
-        "reindex.remote.whitelist",
-        emptyList(),
-        Function.identity(),
-        Property.NodeScope,
-        Property.Deprecated
-    );
-    // The setting below is going to replace the above.
-    // To keep backwards compatibility, the old usage is remained, and it's also used as the fallback for the new usage.
     public static final Setting<List<String>> REMOTE_CLUSTER_ALLOWLIST = Setting.listSetting(
         "reindex.remote.allowlist",
-        REMOTE_CLUSTER_WHITELIST,
+        emptyList(),
         Function.identity(),
         Property.NodeScope
     );