$ git clone -n https://src.fedoraproject.org/rpms/pam_yubico.git /var/lib/mock/f41-build-855391-167123/root/chroot_tmpdir/scmroot/pam_yubico
Cloning into '/var/lib/mock/f41-build-855391-167123/root/chroot_tmpdir/scmroot/pam_yubico'...
$ git fetch origin 21d61834be7458db67e500ffe3be471ebba51a67:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/pam_yubico
 * [new ref]         21d61834be7458db67e500ffe3be471ebba51a67 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 21d6183 Fix C99 compatibility issue