Investigate and reduce amount of 'CACHE' SQL for Groups::GroupMembersController#index

As listed in epic: &3873 (closed), we detected several end-points that have a big amount of CACHE SQL.

Groups::GroupMembersController#create is one of them.

It is also very popular in terms of how many times(count) it is invoked daily.

There are potentially several benefits if we could improve the SQL/Cached_SQL calls for this endpoint:

• from the database CPU cost perspective, 4523052 * 0.0929273990589387 / 3600 = 116 hours. So if we could make some improvements, it would reduce CPU costs.
• reduce memory consumption in Rails application.

json.meta.caller_id.keyword: Descending	Count	Max json.db_cached_count	Average json.db_duration_s
Groups::GroupMembersController#index	66,760	113	0.108