Replace string literals with store definitions in block-editor

[aristath]

Description

Replaces literals with store definitions for the block-editor package(s).
Part of #27088

How has this been tested?

• npm run lint-js packages/block-editor/ no longer throws warnings for these string literals
• tests should be green

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).

[gziolo]

For React Native files I filed an issue some time ago: #27751. It explains in-depth the issue. The gist of it is that @wordpress/block-editor is a lower-level package than @wordpress/edit-post so that creates a cyclic dependency between those two.

We can safely merge only changes in:
packages/block-editor/src/components/use-block-drop-zone/index.js

We should list all remaining files in the issue I referenced. It's a design flow that needs to be addressed separately. This is also why we wanted to replace hardcoded strings with imported objects so we could catch those violations.

[gziolo]

Nice, thank you!

[ellatrix]

Why was this merged with failing tests?