Custom function - freezing dashboard in case of error

[miranov25]

Custom function provide as a text in the unit test working well. In realistic use case in case of failure it was freezing the dashboard:

• https://alice.its.cern.ch/jira/browse/ATO-612?focusedCommentId=292406&page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#comment-292406

Later investigation had shown in case of error ...if widget changed invalid column callback did not propagate further. callback did not return back. -> It influenced given column and derived variables

[miranov25]

Working in realistic use case: https://gitlab.cern.ch/alice-tpc-offline/alice-tpc-notes/-/blob/3ced53d90795b5677040f5f754ca3a8e9be92c0a/JIRA/ATO-609/trackClusterDumpDraw.ipynb

[miranov25]

Unit test OK

-- Docs: https://docs.pytest.org/en/stable/how-to/capture-warnings.html
------------------------------------------------------------------------------------- JSON report --------------------------------------------------------------------------------------
report saved to: test6.json
====================================================================== 37 passed, 7 warnings in 77.02s (0:01:17) =======================================================================

real    1m18.494s
user    9m52.904s
sys     0m40.624s