fix(MSL): raise exception on error in MSL response message

- Replace silent log of error with raising an exception
- Ensure errors in MSL response messages do not go unnoticed
- Prevent continuation on critical MSL response errors
- Improve error handling robustness in MSL class

unshackle/services/Netflix/MSL/__init__.py

@@ -342,7 +342,7 @@ class MSL:
 
             if not (error_display or error_detail):
                 self.log.critical(f"- {error}")
-
+            raise Exception(f"- MSL response message contains an error: {error}")
             # sys.exit(1)
 
         return data["result"]