[BUGFIX] EM: Update button -> display version

Adds the target version of the extension which
needs an update into the title tag of the update
button.

Releases: 6.0, 6.1
Resolves: #45245
Change-Id: Icd5f98407300abf5759554002c1d42b9214a106c
Reviewed-on: https://review.typo3.org/18085
Reviewed-by: Anja Leichsenring
Tested-by: Anja Leichsenring
Reviewed-by: Philipp Gampe
Tested-by: Philipp Gampe
Reviewed-by: Christian Kuhn
Tested-by: Christian Kuhn