Fix buffer_client.py using default timeout_padding (ros#437)

* Fix buffer_client.py using default timeout_padding

fixes ros#436

Co-authored-by: Chris Lalancette <clalancette@openrobotics.org>

tf2_ros_py/tf2_ros/buffer_client.py

@@ -70,14 +70,12 @@ def __init__(
         timeout_padding: Duration = Duration(seconds=2.0)
     ) -> None:
         """
-        .. function:: __init__(ns, check_frequency = 10.0, timeout_padding = rospy.Duration.from_sec(2.0))
+        Constructor.
 
-            Constructor.
-
-            :param node: The ROS2 node.
-            :param ns: The namespace in which to look for a BufferServer.
-            :param check_frequency: How frequently to check for updates to known transforms.
-            :param timeout_padding: A constant timeout to add to blocking calls.
+        :param node: The ROS2 node.
+        :param ns: The namespace in which to look for a BufferServer.
+        :param check_frequency: How frequently to check for updates to known transforms.
+        :param timeout_padding: A constant timeout to add to blocking calls.
         """
         tf2_ros.BufferInterface.__init__(self)
         self.node = node
@@ -226,7 +224,7 @@ def unblock_by_timeout():
             clock = Clock()
             start_time = clock.now()
             timeout = Duration.from_msg(goal.timeout)
-            timeout_padding = Duration(seconds=self.timeout_padding)
+            timeout_padding = self.timeout_padding
             while not send_goal_future.done() and not event.is_set():
                 if clock.now() > start_time + timeout + timeout_padding:
                     break
@@ -243,7 +241,7 @@ def unblock_by_timeout():
 
         event.wait()
 
-        #This shouldn't happen, but could in rare cases where the server hangs
+        # This shouldn't happen, but could in rare cases where the server hangs
         if not send_goal_future.done():
             raise tf2.TimeoutException("The LookupTransform goal sent to the BufferServer did not come back in the specified time. Something is likely wrong with the server.")