[TASK] Ship optional upstream CKEditor5 plugins

With the CKEditor5 unbundling in #102099, we can now ship free (GPL-2
licensed) CKEditor5 modules, that may be useful, for some installations,
without the need to ship them for all installations in a big bundle.

  npm install --save \
        @ckeditor/ckeditor5-highlight@41.4.2 \
        @ckeditor/ckeditor5-language@41.4.2 \
        @ckeditor/ckeditor5-mention@41.4.2
  npm run build

Releases: main, 12.4
Resolves: #101128
Related: #102099
Related: #99670
Change-Id: Ic7b88985c64c59c65ee8502e50d74c3206636893
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/85452


Tested-by: core-ci <typo3@b13.com>
Reviewed-by: Georg Ringer <georg.ringer@gmail.com>
Tested-by: Georg Ringer <georg.ringer@gmail.com>