$ git clone -n https://src.fedoraproject.org/rpms/perl-Devel-Caller.git /var/lib/mock/f45-build-23062-595/root/chroot_tmpdir/scmroot/perl-Devel-Caller
Cloning into '/var/lib/mock/f45-build-23062-595/root/chroot_tmpdir/scmroot/perl-Devel-Caller'...
$ git fetch origin 074824e4ba202ae5ea2b3b3f191ce15eacb44f92:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/perl-Devel-Caller
 * [new ref]         074824e4ba202ae5ea2b3b3f191ce15eacb44f92 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 074824e Perl 5.44 rebuild