[BUGFIX][EM] Fix of last update time after update

The time of the last update in the extension manager was not displayed
correctly immediately after an update, an additional refresh was needed.

Fixes: #46573
Releases: 6.1
Change-Id: I51b0c966ddb3dda522cc68573d440e24273e96bc
Reviewed-on: https://review.typo3.org/19202
Reviewed-by: Christian Kuhn
Tested-by: Christian Kuhn