Remove combine-spws

When using -concatenate-frequency the use of -combine-spws is not necessary anymore.

workflows/linc_calibrator/prep.cwl

@@ -222,8 +222,6 @@ steps:
         source: ndppp_prep_cal/msout
       - id: verbose
         default: true
-      - id: combine-spws
-        default: true
       - id: concatenate-frequency
         default: true
       - id: strategy