[KP] Remove deprecated CoreSetup API

[mshustov]

There are different reasons why the Kibana platform provides deprecated API: to alleviate migration process, legacy API leftovers, experimental API sunsetting, etc.
We are targeting v8.0 release to stabilize the KP API, so it can be considered as a soft deadline to remove deprecated API usage to reduce maintenance burden.
List of plugins using deprecated API in table format

As a part of #66366
I added to deprecated in favour of start contact counterparts:

• savedObjects.getImportExportObjectLimit
• uuid.getInstanceUuid
• status
• metrics

I will mark them as deprecated in a dedicated PR. Any objections?

Other services that we might deprecate in favour of start contract counterparts (should be investigated in #66366):

• HTTP service API:
  • client-side: fetch, delete, get, head, options, patch, post, put, addLoadingCountSource, getLoadingCount$
  • server: auth
• Notifications.toasts
• UiSettings client side

[elasticmachine]

Pinging @elastic/kibana-platform (Team:Platform)

[pgayvallet]

uuid.getInstanceUuid

I feel like it could make sense to need to access this one during the setup phase?

Other services that we might deprecate in favour of start contract counterparts

I think the list makes sense.

[pgayvallet]

Most of those deprecated setup APIs were taken care of, the few remaining are listed in more recent "remove deprecations" issues.

Closing.