Fix typo (ros-navigation#4087)

Fix AttributeError: 'BasicNavigator' object has no attribute '_BasicNavigator__getPathThroughPosesImpl'

Signed-off-by: nfriedrich00 <[email protected]>

Author: nfriedrich00

nav2_simple_commander/nav2_simple_commander/robot_navigator.py

@@ -420,7 +420,7 @@ def _getPathThroughPosesImpl(self, start, goals, planner_id='', use_start=False)
 
     def getPathThroughPoses(self, start, goals, planner_id='', use_start=False):
         """Send a `ComputePathThroughPoses` action request."""
-        rtn = self.__getPathThroughPosesImpl(start, goals, planner_id, use_start)
+        rtn = self._getPathThroughPosesImpl(start, goals, planner_id, use_start)
 
         if self.status != GoalStatus.STATUS_SUCCEEDED:
             self.warn(f'Getting path failed with status code: {self.status}')