Add extension requirement "de.systopia.xcm"

Avoid calling an action (getorcreate) API that's not existed without extension "de.dystopia.xcm"

https://lab.civicrm.org/extensions/inlaypay/-/blob/85a9f02c3519e1759a62dddb7a4e542d64dcb43d/Civi/Inlay/Pay.php#L1350