$ git clone -n https://src.fedoraproject.org/rpms/perl-Sys-Syslog.git /var/lib/mock/f45-build-26341-617/root/chroot_tmpdir/scmroot/perl-Sys-Syslog
Cloning into '/var/lib/mock/f45-build-26341-617/root/chroot_tmpdir/scmroot/perl-Sys-Syslog'...
$ git fetch origin 17994cc0de34fc8bbf4f9c064eabf1076f2870c3:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/perl-Sys-Syslog
 * [new ref]         17994cc0de34fc8bbf4f9c064eabf1076f2870c3 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 17994cc Perl 5.44 re-rebuild of bootstrapped packages