The old upgrade functionality within the extension
manager has been superseded by the upgrade wizard
API of the install tool since core v9. The old API
based on the file class.ext_update.php in extensions
has been marked as discouraged in the docs since then.

Many extensions use the new API successfully. It comes
with much more flexibility and also includes happy
little features like a CLI interface.

The patch drops handling of class.ext_update.php without
further deprecation. Extensions still using that script
should migrate to the new API when preparing core v11
readiness.

Change-Id: I1cb40f1222a37763e8d9549af53520597f739d1a
Resolves: #93083
Releases: master
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/67142


Tested-by: TYPO3com <noreply@typo3.com>
Tested-by: Anja Leichsenring <aleichsenring@ab-softlab.de>
Tested-by: Georg Ringer <georg.ringer@gmail.com>
Tested-by: Christian Kuhn <lolli@schwarzbu.ch>
Reviewed-by: Anja Leichsenring <aleichsenring@ab-softlab.de>
Reviewed-by: Georg Ringer <georg.ringer@gmail.com>
Reviewed-by: Christian Kuhn <lolli@schwarzbu.ch>