Fix last point after interlock

src/ScanPGunVgrid.py

@@ -87,7 +87,9 @@ def main():
             sys.exit(1)
         if topup_test_mode == True and (plc_status[9] == True or bool(trigger_gun.read_attribute("gun_trigger_on").value) == False):
             #print("Interlock dcct booster, stop")
-            scan_stop = x
+            scan_stop = x - scan_step
+            X = X[:-1]
+            Y = Y[:-1]
             break
        
         #print("valore gun: " + str(x))