$ git clone -n https://src.fedoraproject.org/rpms/perl-FileHandle-Unget.git /var/lib/mock/f45-build-23625-598/root/chroot_tmpdir/scmroot/perl-FileHandle-Unget
Cloning into '/var/lib/mock/f45-build-23625-598/root/chroot_tmpdir/scmroot/perl-FileHandle-Unget'...
$ git fetch origin ce908406cc55a47b7070eb9c6279d846fd80185d:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/perl-FileHandle-Unget
 * [new ref]         ce908406cc55a47b7070eb9c6279d846fd80185d -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at ce90840 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild