Installations in composer mode should always
rely on the corresponding mechanisms for
installing extensions.

As consequence, all extensions, manually placed
in `typo3conf/ext`, are no longer evaluated.

Resolves: #96304
Related: #94996
Releases: main
Change-Id: Ic25a7d69c564771cabbb5c240b010161f4b0aca6
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/72592


Tested-by: core-ci <typo3@b13.com>
Tested-by: Helmut Hummel <typo3@helhum.io>
Tested-by: Stefan Bürk <stefan@buerk.tech>
Tested-by: Oliver Bartsch <bo@cedev.de>
Reviewed-by: Benni Mack <benni@typo3.org>
Reviewed-by: Helmut Hummel <typo3@helhum.io>
Reviewed-by: Stefan Bürk <stefan@buerk.tech>
Reviewed-by: Oliver Bartsch <bo@cedev.de>