[8.x] Adds index API requests and responses - part 1

[szabosteve]

Overview

Backports the changes of the following PR to the 8.x branch:
Adds index API requests and responses - part 1 #2979

[github-actions]

Following you can find the validation results for the APIs you have changed.

API	Status	Request	Response
indices.add_block	🟢	2/2	2/2
indices.analyze	🔴	241/242	242/242
indices.clone	🟢	5/5	5/5
indices.close	🟢	49/49	49/49
indices.create	🔴	1042/1129	1129/1129
indices.data_streams_stats	🟢	4/4	4/4
indices.delete_data_lifecycle	⚪	Missing test	Missing test
indices.explain_data_lifecycle	⚪	Missing test	Missing test
indices.get_data_lifecycle	⚪	Missing test	Missing test
indices.get_data_stream	🟢	11/11	11/11
indices.open	🟢	20/20	20/20
indices.put_data_lifecycle	⚪	Missing test	Missing test

You can validate these APIs yourself by using the make validate target.

[lcawl]

LGTM!