[BUGFIX] Prevent PageTypeDecorator from matching index too generously

Pages that have slugs that end with the configured index
are now no longer matched falsely by the PageTypeDecorator.

Resolves: #88633
Releases: master, 9.5
Change-Id: I3af91d65bfbb8ef285bba6c00b6cfe85e0b78f6e
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/61965


Tested-by: TYPO3com <noreply@typo3.com>
Tested-by: Susanne Moog <look@susi.dev>
Tested-by: Benni Mack <benni@typo3.org>
Reviewed-by: Tobi Kretschmann <tobi@tobishome.de>
Reviewed-by: Felix P. <f.pachowsky@neusta.de>
Reviewed-by: Sascha Rademacher <sascha.rademacher+typo3@gmail.com>
Reviewed-by: Markus Klein <markus.klein@typo3.org>
Reviewed-by: Susanne Moog <look@susi.dev>
Reviewed-by: Benni Mack <benni@typo3.org>