$ git clone -n https://src.fedoraproject.org/rpms/qtxdg-tools.git /var/lib/mock/f41-build-840328-160611/root/chroot_tmpdir/scmroot/qtxdg-tools
Cloning into '/var/lib/mock/f41-build-840328-160611/root/chroot_tmpdir/scmroot/qtxdg-tools'...
$ git fetch origin f26116c471e5a800bdaefd8799ecb23235672778:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/qtxdg-tools
 * [new ref]         f26116c471e5a800bdaefd8799ecb23235672778 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at f26116c 4.0.0