Fix some articles being incorrectly marked as outdated

These articles were updated for 4.0 and the API hasn't changed in 4.1.

tutorials/2d/using_tilemaps.rst

@@ -1,5 +1,3 @@
-:article_outdated: True
-
 .. _doc_using_tilemaps:
 
 Using TileMaps

tutorials/animation/animation_track_types.rst

@@ -1,5 +1,3 @@
-:article_outdated: True
-
 .. _doc_animation_track_types:
 
 Animation Track types

tutorials/rendering/multiple_resolutions.rst

@@ -1,5 +1,3 @@
-:article_outdated: True
-
 .. _doc_multiple_resolutions:
 
 Multiple resolutions