Test support of Opensearch

[jpmat296]

This PR is only a test to have an idea on how difficult add of Opensearch support would be.

In this PR, I removed Elasticsearch support and make code changes to have Opensearch instead. And :

• Only module elastic_cluster_health works well (others modules have been removed from CI)
• With only Ansible state-2.16
• Only Opensearch 3.3.0 is tested, with SSL kept enabled (it's default)

Does add of Opensearch support is a good idea ? Or is it better I create a new Git repository community.opensearch ?

[rhysmeister]

Hi @jpmat296 - I don't use OpenSearch, or Elastic much now, so I don't really have an opinion to offer. Not against it... up to you if it makes sense.