Fix cancel button not working in main data directory selector dialog

Closes #219 (closed)

requested review from @ldam

assigned to @kienle

approved this merge request

added 25 commits

• c59d2ec2...637e8fed - 24 commits from branch master
• 510b01cf - Fix the problem

Compare with previous version

enabled an automatic merge when the pipeline for 510b01cf succeeds

merged

mentioned in commit 08d4b24c