Enable Spacer block in production

[geriux]

This enables the Spacer block in production

Fixes #1587

Gutenberg PR -> WordPress/gutenberg#18605

To test:

WordPress iOS -> wordpress-mobile/WordPress-iOS#12970
WordPress Android -> wordpress-mobile/WordPress-Android#10817

Update release notes:

• If there are user facing changes, I have added an item to RELEASE-NOTES.txt.

[SergioEstevao]

Working on iOS!

[marecar3]

Hey @geriux, not sure if I am missing some context but usually the practice is that we update bundle files through the release process.

The release process for the v1.18.0 started yesterday so you can be sure that, if we merge this PR, spacer will be part of the new release bundle.

[geriux]

Hey @geriux, not sure if I am missing some context but usually the practice is that we update bundle files through the release process.

The release process for the v1.18.0 started yesterday so you can be sure that, if we merge this PR, spacer will be part of the new release bundle.

Yup, I updated the bundles so reviewers were able to test the Spacer block in the main apps before merging. It also was a good test as part of my onboarding to know how to generate bundles, etc =)

[maxme]

I'm not sure if there is a process for this, but I'll drop the bundle changes from the PR and keep the gutenberg ref change only.

[maxme]

@geriux the e2e tests seem to fail - can you check it's related to your changes?

[pinarol]

I'll drop the bundle changes from the PR and keep the gutenberg ref change only

Sounds good 👍bundles are usually generated only on release branches, this one was needed just for testing purposes because we needed to verify Spacer block appearing in the block picker while metro is off.

[geriux]

@geriux the e2e tests seem to fail - can you check it's related to your changes?

It shouldn't be but I'll check, thanks!