[BUGFIX] Always process removeButtons in CKEditor5 Migration

The CKEditor5 Migration migrates the current configuration to the
new format, but there is no need to force users into the new format.
To extend compatibility to older configurations the removeButtons
configurtion always needs to be processed.

Resolves: #99471
Releases: main
Change-Id: Ib674732309c0d34b9a5ff0e902cf2bb064c1b69c
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/77267


Reviewed-by: Markus Klein <markus.klein@typo3.org>
Reviewed-by: Benni Mack <benni@typo3.org>
Tested-by: core-ci <typo3@b13.com>
Tested-by: Benni Mack <benni@typo3.org>
Reviewed-by: Frank Nägler <frank.naegler@typo3.com>
Tested-by: Frank Nägler <frank.naegler@typo3.com>