remove unused legacy markdown component

[eokoneyo]

Summary

Removes previous markdown, since all its usage has been migrated to new markdown component.

[eokoneyo]

/ci

[eokoneyo]

/ci

[elasticmachine]

Pinging @elastic/appex-sharedux (Team:SharedUX)

[eokoneyo]

@elasticmachine merge upstream

[eokoneyo]

@elasticmachine merge upstream

[kibana-ci]

💚 Build Succeeded

• Buildkite Build
• Commit: c73222a

Metrics [docs]

Module Count

Fewer modules leads to a faster build time

id	before	after	diff
kibanaReact	268	116	-152

Public APIs missing comments

Total count of every public API that lacks a comment. Target amount is 0. Run node scripts/build_api_docs --plugin [yourplugin] --stats comments for more detailed information.

id	before	after	diff
kibanaReact	121	117	-4

Async chunks

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

id	before	after	diff
kibanaReact	165.6KB	0.0B	-165.6KB

Public APIs missing exports

Total count of every type that is part of your API that should be exported but is not. This will cause broken links in the API documentation system. Target amount is 0. Run node scripts/build_api_docs --plugin [yourplugin] --stats exports for more detailed information.

id	before	after	diff
kibanaReact	3	1	-2

Page load bundle

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

id	before	after	diff
kibanaReact	40.3KB	38.6KB	-1.7KB

Unknown metric groups

API count

id	before	after	diff
kibanaReact	153	149	-4

async chunk count

id	before	after	diff
kibanaReact	2	0	-2

ESLint disabled line counts

id	before	after	diff
kibanaReact	3	0	-3

Total ESLint disabled count

id	before	after	diff
kibanaReact	3	0	-3

History

• 💛 Build #199473 was flaky 3cfb0cf
• 💚 Build #199115 succeeded 6c68ead
• 💔 Build #198972 failed ab1f7fd

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

cc @eokoneyo