[Plugin migration] Update upstream

[VijayanB]

Updated build file to use openserach-7.10.3-SNAPSHOT as upstream.

By submitting this pull request, I confirm that you can use, modify, copy, and redistribute this contribution, under the terms of your choice.

[VijayanB]

curl http://localhost:9200

3c22fb3bf9b7:opendistroforelasticsearch-1.13.1 2 balasvij$ curl http://localhost:9200
{
  "name" : "integTest-0",
  "cluster_name" : "integTest",
  "cluster_uuid" : "NlduXDMESa6u9V2M6UXYNA",
  "version" : {
    "number" : "7.10.3-SNAPSHOT",
    "build_type" : "tar",
    "build_hash" : "f7a7b80fbad8a91403771941b26e246f7b8108d1",
    "build_date" : "2021-03-26T22:11:35.988476Z",
    "build_snapshot" : true,
    "lucene_version" : "8.7.0",
    "minimum_wire_compatibility_version" : "6.8.0",
    "minimum_index_compatibility_version" : "6.0.0-beta1"
  }
}

[saratvemulapalli]

Overall the changes look good to me.
Few minor comments.

[saratvemulapalli]

Minor nit, can we rename es to opensearch

Suggested change

	es_version = System.getProperty("es.version", "7.10.3")
	es_group = "org.opensearch"
	opensearch_version = System.getProperty("es.version", "7.10.3")
	opensearch_group = "org.opensearch"

[VijayanB]

Ack

[saratvemulapalli]

Looks like an unintended comment.

[VijayanB]

Good catch. Thanks.

[VijayanB]

Will rename variables in next PR. Would like to make sure build works with OpenSearch as upstream.

[jmazanec15]

Will file paths be updated in a followup PR?

Also, does Cmake file need to be updated in this PR? https://github.com/opensearch-project/k-NN/blob/main/jni/CMakeLists.txt

[VijayanB]

Will file paths be updated in a followup PR?

Also, does Cmake file need to be updated in this PR? https://github.com/opensearch-project/k-NN/blob/main/jni/CMakeLists.txt

I believe that library or path should nat have impact since we are just updating only the upstream. if not, can you let me know where are we using absolute path instead of relative?

[vamshin]

LGTM! Thanks