TMSS-250: fixed stations -> station_groups according to schema

SAS/TMSS/src/tmss/tmssapp/schemas/simple-observation-scheduling-unit-observation-strategy.json

@@ -24,7 +24,9 @@
         },
         "antenna_set": "HBA_DUAL_INNER",
         "filter": "HBA_110_190",
-        "stations": ["CS001"],
+        "station_groups": [ {
+            "stations": ["CS002", "CS003", "CS004", "CS005", "CS006", "CS007"]
+        }],
         "tile_beam": {
           "direction_type": "J2000",
           "angle1": 0.42,