$ git clone -n https://src.fedoraproject.org/rpms/rubygem-sys-filesystem.git /var/lib/mock/f40-build-2639373-66354/root/chroot_tmpdir/scmroot/rubygem-sys-filesystem
Cloning into '/var/lib/mock/f40-build-2639373-66354/root/chroot_tmpdir/scmroot/rubygem-sys-filesystem'...
$ git fetch origin af346aa24ba34ce4f688ab217115df30b78a88c9:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rubygem-sys-filesystem
 * [new ref]         af346aa24ba34ce4f688ab217115df30b78a88c9 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at af346aa Rebuilt for https://fedoraproject.org/wiki/Fedora_40_Mass_Rebuild