[7.x] [Usage Collection] Remove unused UI Metric APIs (#91620)

[kibanamachine]

Backports the following commits to 7.x:

• [Usage Collection] Remove unused UI Metric APIs ([Usage Collection] Remove unused UI Metric APIs #91620)

[kibanamachine]

💚 Build Succeeded

• continuous-integration/kibana-ci/pull-request
• Commit: 3deb35f
• Storybooks Preview

Metrics [docs]

Async chunks

Total size of all lazy-loaded chunks that will be downloaded as the user navigates the app

id	before	after	diff
ingestPipelines	723.5KB	723.5KB	+2.0B

Page load bundle

Size of the bundles that are downloaded on every page load. Target size is below 100kb

id	before	after	diff
indexPatternFieldEditor	79.1KB	79.3KB	+212.0B
ingestPipelines	26.1KB	26.2KB	+153.0B
usageCollection	10.0KB	9.8KB	-257.0B
total			+108.0B

To update your PR or re-run it, just comment with:
@elasticmachine merge upstream

cc @afharo