$ git clone -n https://src.fedoraproject.org/rpms/maturin.git /var/lib/mock/f42-build-side-1-3498301-45962/root/chroot_tmpdir/scmroot/maturin
Cloning into '/var/lib/mock/f42-build-side-1-3498301-45962/root/chroot_tmpdir/scmroot/maturin'...
$ git fetch origin 437a892e09a1106c8527f38ef1ed677978cd41cb:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/maturin
 * [new ref]         437a892e09a1106c8527f38ef1ed677978cd41cb -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 437a892 Update to version 1.8.3; Fixes RHBZ#2329012