Merge pull request #463 in CASA/casa6 from CAS-13623 to master
* commit '07af1e398268a441df037ca5c162440289dcb4f4':
Closing table before assertion in test_fringefit.py
Removed an unhelpful and inaccurate comment
Added a simple test for FringeJones calibration tables to check consequences of FreqMetaData use
Fringefit task now uses FreqMetaData to get the reference frequency