Merge pull request #480 in CASA/casa6 from CAS-13508 to master
* commit 'c4538d5fa4a3f0ffa8d8a01dd10484f14466389f':
Updated test_iterbot_cube_restart_pbmask and test_interbot_cube_restart_updatedmask to use nearest interpolation as linear interpolation produces poor ch0 psf in serial run for this two-channel data set. Also updated the reference values due to this change.
Modified the unit tests and added two more. Added a new value check parameter (firstcyclethresh) to checkall in imagetestheper
Added unittests to verify CAS-13508 fix and a parameter check in imagetesthelpers
Added back hasConverged for all cases after updatemask to include the masks in the image statistics
Updated test_iterbot_cube_restart_pbmask and test_interbot_cube_restart_updatedmask to use nearest interpolation as linear interpolation produces poor ch0 psf in serial run for this two-channel data set. Also updated the reference values due to this change.
