[TASK] Remove rector/rector from require-dev section

used commands:
   composer remove rector/rector --no-update-with-dependencies

The groundwork to use rector as a integrity check is not yet done.
In order to remove a dependency from the set, the package is removed.

Resolves: #92332
Related: #89785
Releases: master, 10.4
Change-Id: I7b965c9826dc45bb8409d4460e9dcb071aa83c68
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/65750


Tested-by: Simon Gilli <typo3@gilbertsoft.org>
Tested-by: Richard Haeser <richard@richardhaeser.com>
Tested-by: TYPO3com <noreply@typo3.com>
Tested-by: Anja Leichsenring <aleichsenring@ab-softlab.de>
Reviewed-by: Simon Gilli <typo3@gilbertsoft.org>
Reviewed-by: Richard Haeser <richard@richardhaeser.com>
Reviewed-by: Anja Leichsenring <aleichsenring@ab-softlab.de>