Block Settings Menu: Disable 'Move to' if there is only one block.

[getsource]

Description

In the Block Settings Menu, disables "Move to" when there is only one block.

I set it to disabled due to the request in #33029, but while working on it, I noticed that other items in the Block Settings Dropdown aren't displayed when they aren't actionable. Happy to change to that behavior if it's desired.

Fixes: #33029

How has this been tested?

• Check to confirm "Move to" is disabled with one block
• Add another block
• Check to confirm "Move to" is enabled and functions
• Remove one block
• Check to confirm "Move to" is disabled again.

Screenshots

Screen.Recording.2021-07-01.at.23.05.38.mov

Types of changes

Enhancement

Checklist:

• My code is tested.
• My code follows the WordPress code style.
• My code follows the accessibility standards.
• I've tested my changes with keyboard and screen readers.
• My code has proper inline documentation.
• I've included developer documentation if appropriate.
• I've updated all React Native files affected by any refactorings/renamings in this PR (please manually search all *.native.js files for terms that need renaming or removal).

[jorgefilipecosta]

LGTM 👍 Thank you for this fix @getsource!

[mtias]

Indeed, might be fine to skip rendering it entirely.

[getsource]

Thank you @jorgefilipecosta and @mtias !

Indeed, might be fine to skip rendering it entirely.

I like the idea of reducing noise and UI elements when possible, so I added a follow-up PR for consideration: #33158