Docs: Fix typos

[Soean]

This PR fixes some typos in the documentation.

[github-actions]

Flaky tests detected in d0765db.
Some tests passed with failed attempts. The failures may not be related to this commit but are still reported for visibility. See the documentation for more information.

🔍 Workflow run URL: https://github.com/WordPress/gutenberg/actions/runs/3848016070
📝 Reported issues:

• [Flaky Test] results in two remaining blocks and positions the caret at the end of the second block #39805 in specs/editor/various/block-deletion.test.js

[fabiankaegy]

Thanks for these fixes :)