Remove duplicate future handling from send_goal_async (#1532)

A recent change intended to move this logic into a lock context, but
actually ended up duplicating it instead. This fixes that by removing
the duplicated logic outside of the lock. It also preserves the explicit
typing annotation on the future.

Signed-off-by: Nathan Wiebe Neufeldt <[email protected]>

Author: nwn

rclpy/rclpy/action/client.py

@@ -524,7 +524,7 @@ def send_goal_async(
         request = self._action_type.Impl.SendGoalService.Request()
         request.goal_id = self._generate_random_uuid() if goal_uuid is None else goal_uuid
         request.goal = goal
-        future = Future()
+        future: Future[ClientGoalHandle[GoalT, ResultT, FeedbackT]] = Future()
         with self._lock:
             sequence_number = self._client_handle.send_goal_request(request)
             if sequence_number in self._pending_goal_requests:
@@ -541,13 +541,6 @@ def send_goal_async(
             goal_uuid = bytes(request.goal_id.uuid)
             self._feedback_callbacks[goal_uuid] = feedback_callback
 
-        future: Future[ClientGoalHandle[GoalT, ResultT, FeedbackT]] = Future()
-        self._pending_goal_requests[sequence_number] = future
-        self._goal_sequence_number_to_goal_id[sequence_number] = request.goal_id
-        future.add_done_callback(self._remove_pending_goal_request)
-        # Add future so executor is aware
-        self.add_future(future)
-
         return future
 
     def _cancel_goal(self, goal_handle: ClientGoalHandle[GoalT, ResultT, FeedbackT]