Fix linter

Signed-off-by: Addisu Z. Taddese <[email protected]>

nav2_bringup/launch/tb3_gz_simulation_launch.py

@@ -223,7 +223,7 @@ def generate_launch_description():
     # running in headless mode. But currently, the Gazebo command line doesn't
     # take SDF strings for worlds, so the output of xacro needs to be saved into
     # a temporary file and passed to Gazebo.
-    world_sdf = tempfile.mktemp(prefix="nav2_", suffix=".sdf")
+    world_sdf = tempfile.mktemp(prefix='nav2_', suffix='.sdf')
     world_sdf_xacro = ExecuteProcess(
         cmd=['xacro', '-o', world_sdf, ['headless:=', headless], world])
     gazebo_server = IncludeLaunchDescription(