Add bwc version 2.19.4

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

Author: opensearch-ci-bot

.ci/bwcVersions

@@ -46,5 +46,6 @@ BWC_VERSION:
   - "2.19.1"
   - "2.19.2"
   - "2.19.3"
+  - "2.19.4"
   - "3.0.0"
   - "3.1.0"

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

@@ -117,6 +117,7 @@ public class Version implements Comparable<Version>, ToXContentFragment {
     public static final Version V_2_19_1 = new Version(2190199, org.apache.lucene.util.Version.LUCENE_9_12_1);
     public static final Version V_2_19_2 = new Version(2190299, org.apache.lucene.util.Version.LUCENE_9_12_1);
     public static final Version V_2_19_3 = new Version(2190399, org.apache.lucene.util.Version.LUCENE_9_12_2);
+    public static final Version V_2_19_4 = new Version(20190499, org.apache.lucene.util.Version.LUCENE_9_12_2);
     public static final Version V_3_0_0 = new Version(3000099, org.apache.lucene.util.Version.LUCENE_10_1_0);
     public static final Version V_3_1_0 = new Version(3010099, org.apache.lucene.util.Version.LUCENE_10_2_1);
     public static final Version V_3_2_0 = new Version(3020099, org.apache.lucene.util.Version.LUCENE_10_2_2);