[AUTO] Increment version to 2.9.1-SNAPSHOT

[opensearch-trigger-bot]

• Incremented version to 2.9.1-SNAPSHOT.

[junqiu-lei]

The build failure is due to upstream components not found:

> Could not resolve all files for configuration ':zipArchive'.
   > Could not find org.opensearch.plugin:opensearch-knn:2.9.1.0-SNAPSHOT.
     Searched in the following locations:
       - https://repo.maven.apache.org/maven2/org/opensearch/plugin/opensearch-knn/2.9.1.0-SNAPSHOT/maven-metadata.xml
       - https://repo.maven.apache.org/maven2/org/opensearch/plugin/opensearch-knn/2.9.1.0-SNAPSHOT/opensearch-knn-2.9.1.0-SNAPSHOT.pom
       - file:/home/runner/.m2/repository/org/opensearch/plugin/opensearch-knn/2.9.1.0-SNAPSHOT/maven-metadata.xml
       - file:/home/runner/.m2/repository/org/opensearch/plugin/opensearch-knn/2.9.1.0-SNAPSHOT/opensearch-knn-2.9.1.0-SNAPSHOT.pom
       - https://aws.oss.sonatype.org/content/repositories/snapshots/org/opensearch/plugin/opensearch-knn/2.9.1.0-SNAPSHOT/maven-metadata.xml
       - https://aws.oss.sonatype.org/content/repositories/snapshots/org/opensearch/plugin/opensearch-knn/2.9.1.0-SNAPSHOT/opensearch-knn-2.9.1.0-SNAPSHOT.pom
       - https://plugins.gradle.org/m2/org/opensearch/plugin/opensearch-knn/2.9.1.0-SNAPSHOT/maven-metadata.xml
       - https://plugins.gradle.org/m2/org/opensearch/plugin/opensearch-knn/2.9.1.0-SNAPSHOT/opensearch-knn-2.9.1.0-SNAPSHOT.pom
     Required by:
         project :
   > Could not find org.opensearch.plugin:opensearch-ml-plugin:2.9.1.0-SNAPSHOT.
     Searched in the following locations:
       - https://repo.maven.apache.org/maven2/org/opensearch/plugin/opensearch-ml-plugin/2.9.1.0-SNAPSHOT/maven-metadata.xml
       - https://repo.maven.apache.org/maven2/org/opensearch/plugin/opensearch-ml-plugin/2.9.1.0-SNAPSHOT/opensearch-ml-plugin-2.9.1.0-SNAPSHOT.pom
       - file:/home/runner/.m2/repository/org/opensearch/plugin/opensearch-ml-plugin/2.9.1.0-SNAPSHOT/maven-metadata.xml
       - file:/home/runner/.m2/repository/org/opensearch/plugin/opensearch-ml-plugin/2.9.1.0-SNAPSHOT/opensearch-ml-plugin-2.9.1.0-SNAPSHOT.pom
       - https://aws.oss.sonatype.org/content/repositories/snapshots/org/opensearch/plugin/opensearch-ml-plugin/2.9.1.0-SNAPSHOT/maven-metadata.xml
       - https://aws.oss.sonatype.org/content/repositories/snapshots/org/opensearch/plugin/opensearch-ml-plugin/2.9.1.0-SNAPSHOT/opensearch-ml-plugin-2.9.1.0-SNAPSHOT.pom
       - https://plugins.gradle.org/m2/org/opensearch/plugin/opensearch-ml-plugin/2.9.1.0-SNAPSHOT/maven-metadata.xml
       - https://plugins.gradle.org/m2/org/opensearch/plugin/opensearch-ml-plugin/2.9.1.0-SNAPSHOT/opensearch-ml-plugin-2.9.1.0-SNAPSHOT.pom
     Required by:
         project :

knn 2.9.1 PR just got merged:
opensearch-project/k-NN#1008