Update CKEditor 5 to 41.2.0

Copy/paste leftover 🤣

Based on the results from January 29 over at #3379104-35: Add a "CKEditor 5 nightly" GitLab CI job, I already know tests will fail. 😮‍💨

Well that was easy 😄

In a meeting with the CKEditor 5 team just now, there's going to be a 41.2.0 release next week, so let's wait for that 👍

https://github.com/ckeditor/ckeditor5/releases/tag/v41.2.0 is out 👍

Some very interesting new things:

1. CKEditor 5 v41.2.0 introduces the Accessibility Help Dialog, which is something CKEditor 4 also used to have!
2. link: Added the ability to specify allowed URL protocols by introducing the link.allowedProtocols configuration property. Closes #14304. (commit) -> doesn't really affect us because the default (only allowing HTTP/HTTPS/MAILTO) has served us fine so far. But a contrib/custom module may have additional needs, so then this makes sense 👍
3. html-support: Background color style should be properly preserved by GHS while the FontBackgroundColor plugin is enabled. It should also be able to preserve a partly defined style. Closes #15757, #10399. (commit) → I'm sure this will help sites with … more "complex" content
4. paste-from-office: It now should be possible to paste charts from Microsoft Word. Closes #15758. (commit) → surely an important fix for some
5. source-editing: Source editing should not add whitespaces to the pre-formatted code lines. Closes #15084. (commit) → reported by yours truly: https://github.com/ckeditor/ckeditor5/issues/15084 🤓

@jannakha Ohhhh! Well-spotted! Thank you 🫣🙏😄

RE: AccessibilityHelp: I contemplated doing that. I was thinking it'd be preferred to do that in a follow-up issue, because we may want to change the Standard install profile's default text editors to have this button enabled by default…

RE: 10.2/10.3: this will land in 10.3 for sure, because 10.3.0 has not been released yet. This will not be backported to 10.2.0, because it's a major version bump of CKEditor 5, and includes breaking changes.

Thanks, @jannakha! Followed up on that issue.

This issue is now ready for RTBC — and I think @jannakha is uniquely qualified to do so, because she spotted the thing I overlooked! 😄👍

P.S.: are you on Drupal Slack? What's your username there? :)

Oh weird … you're right: 🫣

$ git status -- core/assets/vendor/ckeditor5/
On branch 11.x
Your branch is up to date with 'origin/11.x'.

nothing to commit, working tree clean

$ yarn --cwd core build
<SNIP>

$ git status -- core/assets/vendor/ckeditor5/
On branch 11.x
Your branch is up to date with 'origin/11.x'.

Untracked files:
  (use "git add <file>..." to include in what will be committed)
	core/assets/vendor/ckeditor5/autoformat/translations/

nothing added to commit but untracked files present (use "git add" to track)

The testUnmanagedGitIgnoreWhenGitNotAvailable failure is happening all across core; that's unrelated to this MR.

Repeated #23 locally on top of the branch that @finnsky pushed, and confirmed that I get identical results.

⚠️ I've updated the issue summary to ensure the next CKEditor 5 update doesn't repeat this mistake.