$ git clone -n https://src.fedoraproject.org/rpms/secrets.git /var/lib/mock/f39-build-1565486-37574/root/chroot_tmpdir/scmroot/secrets
Cloning into '/var/lib/mock/f39-build-1565486-37574/root/chroot_tmpdir/scmroot/secrets'...
$ git fetch origin 8623c311a94d1f57ed957e3658be989e99857253:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/secrets
 * [new ref]         8623c311a94d1f57ed957e3658be989e99857253 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 8623c31 build: Update to 8.0