Fix MarkdownEditor suggestions filtering bug and allow lazy-loading suggestions

[iansan5653]

1. Fixs a bug where suggestions values shorter than the filter query would always appear first in the list, even if they don't match the query. This fixes MarkdownEditor suggestions break when querying by 3 or more characters #2423
2. Adds support for lazy-loading suggestions data so it doesn't have to be ready when the editor is mounted. This was done by changing the prop types to optionally accept an async function instead of a plain old array. This way, the consumer can wait to make an API request until the MarkdownEditor asks for the data. Then they can cache the data for future rendering. The new prop types look like emojiSuggestions?: Emoji[] | (() => Promise<Emoji[]>). This resolves MarkdownEditor should allow lazy-loading suggestions #2422
3. [minor] Improves the MarkdownEditor test suite to perform the mocking of offsetHeight on the HTMLElement prototype in a beforeAll instead of on the element instances themselves in a layoutEffect. This is far less buggy and removes any chance of race conditions (which I was encountering when moving to async event handlers for rendering suggestions).

[changeset-bot]

🦋 Changeset detected

Latest commit: d832344

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

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@primer/react	Patch

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[github-actions]

size-limit report 📦

Path	Size
dist/browser.esm.js	77.65 KB (0%)
dist/browser.umd.js	78.31 KB (0%)

[joshblack]

🥳

[Lukeghenco]

The lazy loading of emojis, references and suggestions is killer.

The bug fixes here are stuff we've logged in the pull requests app we are building too. This should resolve our same issues.

Thanks for leading the charge here.

[siddharthkp]

Scoped to drafts, ship it