Fix deletion of device maintenance action in actions timeline

Goal of this MR:

• fix the deletion of the device maintenance action from the actions timeline after successful deletion from backend

Fixes #168 (closed)

added Bug Frontend UI/UX + 1 deleted label

requested review from @nils.brinckmann

assigned to @marc.hanisch

approved this merge request

Feel free to merge!

(But still I wonder a little bit if react + typescript would have checked for a wrong event...)

resolved all threads

merged

mentioned in commit bee788cb

resolved all threads