Fix: UR Parameter Generation (#277)

Use merge instead of update to prevent clobbering parameters

Author: luis-camero

clearpath_generator_common/clearpath_generator_common/param/manipulators.py

@@ -131,7 +131,9 @@ def generate_parameters(self, use_sim_time: bool = False) -> None:
                             parameters={}
                         )
                         update_rate_param_file.read()
-                        updated_parameters.update(update_rate_param_file.parameters)
+                        updated_parameters = merge_dict(
+                            updated_parameters,
+                            update_rate_param_file.parameters)
                     except Exception as e:
                         print(f'Unable to get UniversalRobots {arm.ur_type}_'
                               f'update_rate.yaml parameter file: {e.args[0]}')