[!!!][TASK] Remove deprecated TypoScript settings

- config.spamProtectEmailAddresses = ascii
- config.xhtmlDoctype
- config.removePageCss
- plugin.*._CSS_PAGE_STYLE
- config.baseURL

Resolves: #100996
Related: #100963
Related: #99170
Related: #90044
Related: #99416
Related: #99050
Releases: main
Change-Id: Ib6153755e211e7a80ae17abc03493a205f718748
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/79259


Reviewed-by: Christian Kuhn <lolli@schwarzbu.ch>
Reviewed-by: Benni Mack <benni@typo3.org>
Tested-by: Christian Kuhn <lolli@schwarzbu.ch>
Tested-by: Oliver Bartsch <bo@cedev.de>
Tested-by: Benni Mack <benni@typo3.org>
Tested-by: core-ci <typo3@b13.com>
Reviewed-by: Oliver Bartsch <bo@cedev.de>
Reviewed-by: Thomas Hohn <tho@gyldendal.dk>