Simplify usage

pymoveit2/gripper_command.py

@@ -207,7 +207,7 @@ def force_reset_executing_state(self):
         self.__is_motion_requested = False
         self.__is_executing = False
 
-    def wait_until_executed(self):
+    def wait_until_executed(self) -> bool:
         """
         Wait until the previously requested motion is finalised through either a success or failure.
         """
@@ -216,10 +216,11 @@ def wait_until_executed(self):
             self._node.get_logger().warn(
                 "Cannot wait until motion is executed (no motion is in progress)."
             )
-            return
+            return False
 
         while self.__is_motion_requested or self.__is_executing:
             self.__wait_until_executed_rate.sleep()
+        return True
 
     def __joint_state_callback(self, msg: JointState):
         # Update only if all relevant joints are included in the message

pymoveit2/gripper_interface.py

@@ -175,7 +175,7 @@ def force_reset_executing_state(self):
 
         self._interface.force_reset_executing_state(self=self)
 
-    def wait_until_executed(self):
+    def wait_until_executed(self) -> bool:
         """
         Wait until the previously requested motion is finalised through either a success or failure.
         """
@@ -186,6 +186,6 @@ def wait_until_executed(self):
             self._node.get_logger().error(
                 f"Unable to wait until a motion is executed because the appropriate interface cannot be determined."
             )
-            return
+            return False
 
-        self._interface.wait_until_executed(self=self)
+        return self._interface.wait_until_executed(self=self)