Fix class doc for TileMap navigation visibility mode

fix small copy&paste error

doc/classes/TileMap.xml

@@ -365,7 +365,7 @@
 			Show or hide the TileMap's collision shapes. If set to [constant VISIBILITY_MODE_DEFAULT], this depends on the show collision debug settings.
 		</member>
 		<member name="navigation_visibility_mode" type="int" setter="set_navigation_visibility_mode" getter="get_navigation_visibility_mode" enum="TileMap.VisibilityMode" default="0">
-			Show or hide the TileMap's collision shapes. If set to [constant VISIBILITY_MODE_DEFAULT], this depends on the show navigation debug settings.
+			Show or hide the TileMap's navigation meshes. If set to [constant VISIBILITY_MODE_DEFAULT], this depends on the show navigation debug settings.
 		</member>
 		<member name="tile_set" type="TileSet" setter="set_tileset" getter="get_tileset">
 			The assigned [TileSet].