Increment version to 2.19.4-SNAPSHOT

Signed-off-by: opensearch-ci-bot <[email protected]>

Author: opensearch-ci-bot

build.gradle

@@ -9,7 +9,7 @@ import java.util.stream.Collectors
 
 buildscript {
   ext {
-    opensearch_version = System.getProperty("opensearch.version", "2.19.3-SNAPSHOT")
+    opensearch_version = System.getProperty("opensearch.version", "2.19.4-SNAPSHOT")
     isSnapshot = "true" == System.getProperty("build.snapshot", "true")
     buildVersionQualifier = System.getProperty("build.version_qualifier", "")
     version_tokens = opensearch_version.tokenize('-')