Add api.haxe.org update to release checklist

extra/release-checklist.txt

@@ -23,6 +23,7 @@
 	- If everything was working, run the command again without `--dry`
 - Update https://github.com/HaxeFoundation/haxe.org/blob/staging/downloads/versions.json
 - Wait for staging to update, check everything related to release and merge to master
+- Update https://github.com/HaxeFoundation/api.haxe.org/blob/master/theme/templates/topbar.mtt
 
 # Cleanup