Fix missing newline at end of file in tutorials index

Signed-off-by: bekirbostanci <bekirbostanci@gmail.com>

Author: bekirbostanci

tutorials/index.rst

@@ -30,4 +30,4 @@ Nav2 Tutorials
    docs/route_server_tools.rst
    docs/route_server_tools/navigation2_route_tool.rst
    docs/route_server_tools/route_graph_generation_lif_editor.rst
-   docs/route_server_tools/route_graph_generation.rst
+   docs/route_server_tools/route_graph_generation.rst