$ git clone -n https://src.fedoraproject.org/rpms/sexpp.git /var/lib/mock/f38-build-side-42-init-devel-1407186-31283/root/chroot_tmpdir/scmroot/sexpp
Cloning into '/var/lib/mock/f38-build-side-42-init-devel-1407186-31283/root/chroot_tmpdir/scmroot/sexpp'...
$ git fetch origin dd63299e2f23a6d4a6f3eab01f5209551aee2cea:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/sexpp
 * [new ref]         dd63299e2f23a6d4a6f3eab01f5209551aee2cea -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at dd63299 import from review #2216484