Add PHPCompatibility check to CI
This will make sure an FD version does not use PHP syntax which is newer than the minimum PHP version for this FD version.
See https://gitlab.fusiondirectory.org/fusiondirectory/fd/-/issues/6167
This will make sure an FD version does not use PHP syntax which is newer than the minimum PHP version for this FD version.
See https://gitlab.fusiondirectory.org/fusiondirectory/fd/-/issues/6167