[BUGFIX] Prevent uninstall of an extension during update

This patch removes the uninstall process before an extension is updated.

Resolves: #51572
Releases: 6.1
Change-Id: I61400e9568986d3bbacc3a0a7ad53a4498f3c091
Reviewed-on: http://review.typo3.org/31329
Reviewed-by: Stefano Kowalke <blueduck@gmx.net>
Reviewed-by: Wouter Wolters <typo3@wouterwolters.nl>
Reviewed-by: Markus Klein <klein.t3@reelworx.at>
Tested-by: Markus Klein <klein.t3@reelworx.at>
Reviewed-by: Christian Kuhn <lolli@schwarzbu.ch>
Tested-by: Christian Kuhn <lolli@schwarzbu.ch>