[TASK] Make the whole update button in extension manager clickable

The click area of the update button in extension manager was to small.
The click handler is now assigned to the whole button.

Change-Id: I8b2103dcbde5dcc37a7968780719abca384528a1
Resolves: #76136
Releases: master, 7.6
Reviewed-on: https://review.typo3.org/48092


Tested-by: Riccardo De Contardi <erredeco@gmail.com>
Reviewed-by: Christian Kuhn <lolli@schwarzbu.ch>
Tested-by: Christian Kuhn <lolli@schwarzbu.ch>
Reviewed-by: Nicole Cordes <typo3@cordes.co>
Tested-by: Nicole Cordes <typo3@cordes.co>