Update dependency org.elasticsearch:elasticsearch to v9.1.5 (#3610)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

flink-connectors/flink-connector-elasticsearch-base/pom.xml

@@ -36,7 +36,7 @@ under the License.
 
 	<!-- Allow users to pass custom connector versions -->
 	<properties>
-		<elasticsearch.version>9.1.4</elasticsearch.version>
+		<elasticsearch.version>9.1.5</elasticsearch.version>
 	</properties>
 
 	<dependencies>