$ git clone -n https://src.fedoraproject.org/rpms/capnproto.git /var/lib/mock/f45-build-4115-330/root/chroot_tmpdir/scmroot/capnproto
Cloning into '/var/lib/mock/f45-build-4115-330/root/chroot_tmpdir/scmroot/capnproto'...
$ git fetch origin f64075f53e862f742a048f1ff6e2e1904cb6a1eb:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/capnproto
 * [new ref]         f64075f53e862f742a048f1ff6e2e1904cb6a1eb -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at f64075f Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild