[FEATURE] Add integration tests for all clients to test against Amazon OpenSearch Service and Amazon OpenSearch Serverless Service

[harshavamsi]

Is your feature request related to a problem?

Given the recent troubles in opensearch-project/opensearch-py#278, I propose to add github workflow integration tests that tests against Amazon OpenSearch service.

What solution would you like?

Similar to how we run integration tests today that pull in OpenSearch locally, I propose that Amazon sets up test infrastructure to test against the Managed OpenSearch service.

• [FEATURE] Run integration tests against an AWS instance of OpenSearch / Serverless opensearch-java#1101

[dblock]

There were some discussions about this in acm19/aws-request-signing-apache-interceptor#40 attempting to use mock infrastructure without much success.