Resolve broken GitHub repo sources (#4244)

Signed-off-by: Emmanuel Ferdman <emmanuelferdman@gmail.com>

Author: emmanuel-ferdman

areas-of-d-usage.dd

@@ -92,8 +92,8 @@ $(AREA_SECTION3 $(LNAME2 games, Games), $(ARTICLE_FA_ICON gamepad),
     Many pure-D open source projects show the rising popularity
     of D among game developers.
     Examples are the 3D game engine
-    $(HTTP https://github.com/gecko0307/dagon, Dagon) and the  cross-platform D game development engine
-    $(HTTPS https://github.com/MrcSnm/HipremeEngine, HipremeEngine).
+    $(HTTPS github.com/gecko0307/dagon, Dagon) and the  cross-platform D game development engine
+    $(HTTPS github.com/MrcSnm/HipremeEngine, HipremeEngine).
 )
 
 $(AREA_SECTION3 $(LNAME2 web, Web applications), $(ARTICLE_FA_ICON cloud),