$ git clone -n https://src.fedoraproject.org/rpms/perl-Sys-Hostname-Long.git /var/lib/mock/f45-build-26362-617/root/chroot_tmpdir/scmroot/perl-Sys-Hostname-Long
Cloning into '/var/lib/mock/f45-build-26362-617/root/chroot_tmpdir/scmroot/perl-Sys-Hostname-Long'...
$ git fetch origin 0267a8369effc5cdb37a0a1df657e888889f7c29:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/perl-Sys-Hostname-Long
 * [new ref]         0267a8369effc5cdb37a0a1df657e888889f7c29 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 0267a83 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild