[AUTO] [main] Add bwc version 2.18.1. (opensearch-project#16573)

* Add bwc version 2.18.1

Signed-off-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>

* Update Version.java

Signed-off-by: Andriy Redko <andriy.redko@aiven.io>

---------

Signed-off-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>
Signed-off-by: Andriy Redko <andriy.redko@aiven.io>
Co-authored-by: opensearch-ci-bot <83309141+opensearch-ci-bot@users.noreply.github.com>
Co-authored-by: Andriy Redko <andriy.redko@aiven.io>

Author: 3 people

.ci/bwcVersions

@@ -41,4 +41,5 @@ BWC_VERSION:
   - "2.17.1"
   - "2.17.2"
   - "2.18.0"
+  - "2.18.1"
   - "2.19.0"

libs/core/src/main/java/org/opensearch/Version.java

@@ -112,6 +112,7 @@ public class Version implements Comparable<Version>, ToXContentFragment {
     public static final Version V_2_17_1 = new Version(2170199, org.apache.lucene.util.Version.LUCENE_9_11_1);
     public static final Version V_2_17_2 = new Version(2170299, org.apache.lucene.util.Version.LUCENE_9_11_1);
     public static final Version V_2_18_0 = new Version(2180099, org.apache.lucene.util.Version.LUCENE_9_12_0);
+    public static final Version V_2_18_1 = new Version(2180199, org.apache.lucene.util.Version.LUCENE_9_12_0);
     public static final Version V_3_0_0 = new Version(3000099, org.apache.lucene.util.Version.LUCENE_9_12_0);
     public static final Version V_2_19_0 = new Version(2190099, org.apache.lucene.util.Version.LUCENE_9_12_0);
     public static final Version CURRENT = V_3_0_0;