[CLEANUP] Drop the closing PHP tags

This change drop the closing PHP tags both from the extension classes as well
as from the generated files.

This reflects the current version of the TYPO3 CGL.

Change-Id: Ic107d1406db150be05c59e7dcd8bb539745074d9
Resolves: #58229
Releases: 6.2
Reviewed-on: https://review.typo3.org/29674
Reviewed-by: Nico de Haen
Tested-by: Nico de Haen