Merge in CASA/casa6 from CAS-14417 to master
* commit '5415115a5ffd466b56ce96afce6383a48c610642':
CAS-14417: modified tests with channel selection to execute tsdimaging properly
CASA-14417: fixed the regression test of M100/SD
CAS-14417: added some tests for the interpolation parameter
CAS-14417: modified tests to change default interpolation parameter from nearest to linear