Refs #8374 EQSANS Tests no longer leave files behind

EQSANSTransAPIv2.py, EQSANSBeamCurrentAPIv2.py, EQSANSDarkCurrentAPIv2.py, EQSANSEffAPIv2.py, EQSANSIQOutputAPIv2.py, EQSANSProcessedEffAPIv2.py and EQSANSSolidAPIv2.py have had cleanup implemented, removing all the files they leave behind.