Add lease to graph_nav (#141)

* Add lease to graph_nav

* fixed lint error from pre-commit

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Co-authored-by: Dan Rosenstein <danrose_microsoft>

spot_wrapper/spot_graph_nav.py

@@ -293,6 +293,9 @@ def set_initial_localization_waypoint(self, *args):
             self._logger.error("Failed to find waypoint id.")
             return
 
+        self._lease = self._get_lease()
+        self._lease_keepalive = LeaseKeepAlive(self._lease_client)
+
         robot_state = self._robot_state_client.get_robot_state()
         current_odom_tform_body = get_odom_tform_body(robot_state.kinematic_state.transforms_snapshot).to_proto()
         # Create an initial localization to the specified waypoint as the identity.