Index Patterns page gets fields for all index patterns when only needs titles

[LeeDr]

Kibana version: 7.13.0

Elasticsearch version: 7.13.0

Server OS version: n/a

Browser version: n/a

Browser OS version: n/a

Original install method (e.g. download page, yum, from source, etc.): tar.gz build

Describe the bug: When going to Stack Mgmt > Kibana > Index Patterns, the page is only going to show a paginated list of names (default of 10 per page) but it appears to fetch all the field info for all index patterns. When you click on an index pattern and its going to show all the fields seems like the appropriate time to fetch all the field info.
On a system with only a few index patterns it won't be noticed, but with lots of index patterns, including CCS from remote clusters, it could become a problem.
I noticed this issue because the list of index patterns weren't loading for me. It's because I had paused my remote CCS cluster.

Steps to reproduce:

1. create a few index patterns. Installing the 3 sample data sets would do
2. open browser network tab
3. go to Stack Management > Index Patterns
4. observer the requests like;

Request URL: https://localhost:5601/api/index_patterns/_fields_for_wildcard?pattern=filebeat-*&meta_fields=_source&meta_fields=_id&meta_fields=_type&meta_fields=_index&meta_fields=_score

Expected behavior: I'm thinking it probably should make the fields request only for the one index pattern I click on. The request to get the index pattern titles happens before the requests for the fields;
https://localhost:5601/api/saved_objects/_find?fields=title&per_page=10000&type=index-pattern

Screenshots (if relevant):

Errors in browser console (if relevant):

Provide logs and/or server output (if relevant):

Any additional context:

[elasticmachine]

Pinging @elastic/kibana-app-services (Team:AppServices)