Bump org.opensearch.client:opensearch-java from 2.20.0 to 2.21.0 (#1143)

Bumps [org.opensearch.client:opensearch-java](https://github.com/opensearch-project/opensearch-java) from 2.20.0 to 2.21.0.
- [Release notes](https://github.com/opensearch-project/opensearch-java/releases)
- [Changelog](https://github.com/opensearch-project/opensearch-java/blob/main/CHANGELOG.md)
- [Commits](opensearch-project/opensearch-java@v2.20.0...v2.21.0)

---
updated-dependencies:
- dependency-name: org.opensearch.client:opensearch-java
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

pom.xml

@@ -407,7 +407,7 @@
     <dependency>
       <groupId>org.opensearch.client</groupId>
       <artifactId>opensearch-java</artifactId>
-      <version>2.20.0</version>
+      <version>2.21.0</version>
     </dependency>
     <dependency>
       <groupId>software.amazon.awssdk</groupId>