$ git clone -n https://src.fedoraproject.org/rpms/perl-Cache-Mmap.git /var/lib/mock/f45-build-22096-589/root/chroot_tmpdir/scmroot/perl-Cache-Mmap
Cloning into '/var/lib/mock/f45-build-22096-589/root/chroot_tmpdir/scmroot/perl-Cache-Mmap'...
$ git fetch origin e379d82c1360f1b3b0001027add45857fbc2f34b:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/perl-Cache-Mmap
 * [new ref]         e379d82c1360f1b3b0001027add45857fbc2f34b -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at e379d82 Perl 5.44 rebuild