pylint: fix false positive for "catching-non-exception"
pylint: fix false positive for "catching-non-exception"

Pocketlint uses error description when catching false positives
and it has changed.

rvykydal/blivet,rhinstaller/blivet,vojtechtrefny/blivet,vojtechtrefny/blivet,jkonecny12/blivet,rvykydal/blivet,rhinstaller/blivet,jkonecny12/blivet