Backport bugfixes from Gutenberg into Core for WP 5.9.3

[audrasjb]

This ticket aims to track backports needed from Gutenberg to Core for WP 5.9.3.

[audrasjb]

@mamaduka here is a tracking ticket for Gutenberg backports.
You can refer to this ticket in the incoming PR, and I can handle the related commit(s) :)

Backports changes from ​https://github.com/WordPress/gutenberg/pull/38891.

The package update will include the block modifications from the PR.

Trac ticket: https://core.trac.wordpress.org/ticket/55474

Backports changes from ​https://github.com/WordPress/gutenberg/pull/39164.

Props @ndiego, @alexstine, @c4rl0sbr4v0

Trac ticket: https://core.trac.wordpress.org/ticket/55474

Updated packages:

 - @wordpress/block-directory@3.0.29
 - @wordpress/block-library@6.0.28
 - @wordpress/customize-widgets@2.0.29
 - @wordpress/edit-post@5.0.29
 - @wordpress/edit-site@3.0.29
 - @wordpress/edit-widgets@3.1.24

Trac ticket: https://core.trac.wordpress.org/ticket/55474

Do not merge this; the package-lock.json has too many changes.

@audrasjb, it looks like the previous package update was only ​committed into the 5.9 branch.

I see two options here:

A) We can cherry-pick this commit into the trunk and follow the default git flow.
B) I can checkout and create PR for the 5.9 branch.

Let me know which option do you prefer.

@Mamaduka hmm I'm not 100% sure we only want to commit this to branch 5.9.
In 5.9.1 we also updated packages for trunk: https://core.trac.wordpress.org/changeset/52765

@audrasjb correct, but we forgot to do the same for 5.9.2.

Should we go with option A?

I can also try updating packages in two steps, bump for 5.9.2 and then 5.9.3.

[audrasjb]

In 53012:

Editor: Use wp_unique_id() instead of uniqid() to generate CSS class names.

Backports changes from ​https://github.com/WordPress/gutenberg/pull/38891.
See ​https://github.com/WordPress/gutenberg/issues/38889.

Props westonruter, mamaduka.
See #55474.

Committed in https://core.trac.wordpress.org/changeset/53012

[audrasjb]

In 53013:

Editor: Use wp_unique_id() instead of uniqid() to generate CSS class names.

Backports changes from ​https://github.com/WordPress/gutenberg/pull/38891.
See ​https://github.com/WordPress/gutenberg/issues/38889.

Props westonruter, mamaduka.
Merges [53012] to the 5.9 branch.
See #55474.

I pinged @jorgefilipecosta who handled packages updates for the 5.9.2 security release, just to confirm we're making the right decision :)

[audrasjb]

In 53015:

Editor: Change location of block support styles in wp_head.

Backports changes from ​https://github.com/WordPress/gutenberg/pull/39164.

Props ndiego, alexstine, cbravobernal, mamaduka.
See #55474.

Committed in https://core.trac.wordpress.org/changeset/53015

[audrasjb]

In 53017:

Editor: Change location of block support styles in wp_head.

Backports changes from ​https://github.com/WordPress/gutenberg/pull/39164.

Props ndiego, alexstine, cbravobernal, mamaduka.
Merges [53015] to the 5.9 branch.
See #55474.

After discussing the issue with @jorgefilipecosta, I went with option B.

[audrasjb]

#55163 was marked as a duplicate.

[audrasjb]

In 53030:

Update WordPress packages for 5.9.3.

Updated packages:

• @wordpress/block-directory@3.0.29
• @wordpress/block-library@6.0.28
• @wordpress/customize-widgets@2.0.29
• @wordpress/edit-post@5.0.29
• @wordpress/edit-site@3.0.29
• @wordpress/edit-widgets@3.1.24

Props mamaduka, jorgefilipecosta.
Fixes #55474.

Committed in https://core.trac.wordpress.org/changeset/53030