Investigate upgrading Elasticsearch from 7.10 to Opensearch 2.X

[maxsibilla]

Related HuBMAP card - https://github.com/orgs/hubmapconsortium/projects/40/views/1?filterQuery=opensearch&pane=issue&itemId=66590343

The primary changes will more than likely be made in the submodule search-adaptor's es_writer.py. I do not think file-default-config and search-default-config yaml files will need to be modified as their dynamic templates should still be supported.

AWS notes regarding breaking changes:
https://docs.aws.amazon.com/opensearch-service/latest/developerguide/version-migration.html
https://opensearch.org/docs/latest/breaking-changes/

We will probably need to upgrade the existing AWS domain from 7.10 to Opensearch 1.3 then we should be able to upgrade from that to 2.x. In the meantime we can spin up a temporary domain to test Search API changes against.
Potential configuration for temporary Opensearch 2.x domain -