Dismiss bottom sheet on return key submit

[guarani]

Addresses #1164

To test: See WordPress/gutenberg#20848

PR submission checklist:

• I have considered adding unit tests where possible.
• I have considered if this change warrants user-facing release notes and have added them to RELEASE-NOTES.txt if necessary.

[guarani]

Since using a forked Gutenberg here, this PR needs to be updated before merging.

[mchowning]

What do you think about adding a release note for this change?

[guarani]

What do you think about adding a release note for this change?

@mchowning, good question. I'm leaning towards this being too trivial of a change to warrant inclusion in the release notes, but I could be wrong. If we were going to add it, it could be something like this:

"Block Editor: When editing link settings, tapping the keyboard return button now closes the settings panel as well as closing the keyboard."

[mchowning]

I'm leaning towards this being too trivial of a change to warrant inclusion in the release notes

It seems like a user-facing change to me, so I think it should be added to the release notes. Your suggested release note sounds good to me.

[mchowning]

Working well! Nice job!