Fix small error in readme
Fix small error in readme

no drop-in see changes required and described in the readme
and this gist:
https://gist.github.com/tmolitor-stud-tu/a1e877a7d75c07c2163c3ce1e0347881

tmolitor-stud-tu/mod_push_appserver,tmolitor-stud-tu/mod_push_appserver