Fixup auto-assignable tasks when limits change.

The air wing config was fixing the main `mission_types` field, but the
`auto_assignable_mission_types` property had already been set. Update
that field whenever the `mission_types` are changed.

Fixes https://github.com/dcs-liberation/dcs_liberation/issues/1515

qt_ui/windows/AirWingConfigurationDialog.py

@@ -158,7 +158,9 @@ class SquadronConfigurationBox(QGroupBox):
         self.squadron.pilot_pool = [
             Pilot(n, player=True) for n in player_names
         ] + self.squadron.pilot_pool
-        self.squadron.mission_types = tuple(self.allowed_missions.allowed_mission_types)
+        self.squadron.set_allowed_mission_types(
+            self.allowed_missions.allowed_mission_types
+        )
         return self.squadron