$ git clone -n https://src.fedoraproject.org/rpms/perl-Crypt-U2F-Server.git /var/lib/mock/f41-build-819296-151605/root/chroot_tmpdir/scmroot/perl-Crypt-U2F-Server
Cloning into '/var/lib/mock/f41-build-819296-151605/root/chroot_tmpdir/scmroot/perl-Crypt-U2F-Server'...
$ git fetch origin a43e0d9f3a42979972807b9cddb3a40ea50f0120:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/perl-Crypt-U2F-Server
 * [new ref]         a43e0d9f3a42979972807b9cddb3a40ea50f0120 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at a43e0d9 Initial import