Pull request #573: CAS-13722: fix the subplot=22 option in plotbandpass
Merge in CASA/casa6 from CAS-13722 to master
* commit '1fd93e72e954d16e58f4d5749a1cca03157b93e5':
CAS-13722: silence mpl deprecation warning
CAS-13722: fix typo in variable
CAS-13722 fix subplot=22 option in plotbandpass
CAS-13722 clear axes dictionary after clearing a figure