Moved markdown to kibana_react shim plugin

[lizozom]

Summary

Moved markdown to kibana_react shim plugin

Dev Docs

Markdown

Old:

import { Markdown } from 'ui/markdown/markdown';

New:

import { Markdown } from '../kibana_react/public';

MarkdownSimple

Old:

import { MarkdownSimple } from 'ui/markdown';

New:

import { MarkdownSimple } from '../kibana_react/public';

Checklist

Use strikethroughs to remove checklist items you don't feel are applicable to this PR.

• This was checked for cross-browser compatibility, including a check against IE11
• Any text added follows EUI's writing guidelines, uses sentence case text and includes i18n support
• Documentation was added for features that require explanation or tutorials
• Unit or functional tests were updated or added to match the most common scenarios
• This was checked for keyboard-only and screenreader accessibility

For maintainers

• This was checked for breaking API changes and was labeled appropriately
• This includes a feature addition or change that requires a release note and was labeled appropriately

[elasticmachine]

💔 Build Failed

• continuous-integration/kibana-ci/pull-request

[lizozom]

retest

[elasticmachine]

💚 Build Succeeded

• continuous-integration/kibana-ci/pull-request

[cchaos]

I think the whole github_markdown.scss file can be removed. I'm not finding it used anywhere.

[lizozom]

@cchaos deleted the unused css

[lukeelmers]

Dev docs above says

import { Markdown, MarkdownSimple } from '../data/public';

I'm assuming this is supposed to be:

import { Markdown, MarkdownSimple } from '../kibana_react/public'`;

?

[lukeelmers]

We should consider instead adding the docs to #39907 since this is part of migration efforts. This update probably doesn't need its own dedicated section in the API changes blog post.

[cchaos]

SASS lgtm

[elasticmachine]

💚 Build Succeeded

• continuous-integration/kibana-ci/pull-request

[lizozom]

@lukeelmers
(a) Yes! fixed
(b) We spoke about it on our team meeting. We suggested keeping docs on each issue for clarity and ease of review. I'll remove the release_note:docs tag here, and like with every version, I will go over my issues before 7.4 is release and copy all relevant pieces. Does that sound right?

[alexwizp]

LGTM. Thanks

[elasticmachine]

💚 Build Succeeded

• continuous-integration/kibana-ci/pull-request

[lukeelmers]

I'll remove the release_note:docs tag here, and like with every version, I will go over my issues before 7.4 is release and copy all relevant pieces. Does that sound right?

Yep, that's all I meant :) I think it is still valuable to have the dev docs on each issue, I just felt we can add release_note:skip to this one, and copy the notes over to #39907 as well