[TASK] Use the term "Page TSconfig" consistently in the BE

Following the TYPO3 documentation and the TYPO3 content style guide (in
particular the section "Spelling, terms and glossary"), the BE now uses
the term "Page TSconfig" consistently.

Resolves: #100244
Releases: main
Change-Id: I46bdeda149a1e9e1f77f0309ade15dedd1ccac45
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/78207


Reviewed-by: Benni Mack <benni@typo3.org>
Tested-by: core-ci <typo3@b13.com>
Tested-by: Nikita Hovratov <nikita.h@live.de>
Reviewed-by: Nikita Hovratov <nikita.h@live.de>
Tested-by: Benni Mack <benni@typo3.org>