[TASK] Allow to override RTE config presets via PageTS

Reorder the steps to load the RTE configuration, so that presets can be
overridden by additional PageTS configuration.

Resolves: #81882
Releases: master, 8.7
Change-Id: I0189822f8a4a0cf3b8293d6651eac4f8b5159566
Reviewed-on: https://review.typo3.org/53531


Tested-by: TYPO3com <no-reply@typo3.com>
Reviewed-by: Benni Mack <benni@typo3.org>
Tested-by: Benni Mack <benni@typo3.org>
Reviewed-by: Frans Saris <franssaris@gmail.com>
Reviewed-by: Andreas Fernandez <typo3@scripting-base.de>
Tested-by: Andreas Fernandez <typo3@scripting-base.de>