$ git clone -n https://src.fedoraproject.org/rpms/rust-libcst.git /var/lib/mock/f40-build-2137640-50828/root/chroot_tmpdir/scmroot/rust-libcst
Cloning into '/var/lib/mock/f40-build-2137640-50828/root/chroot_tmpdir/scmroot/rust-libcst'...
$ git fetch origin 317704bab819695e115da5946e35f91fe1ec7fb9:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-libcst
 * [new ref]         317704bab819695e115da5946e35f91fe1ec7fb9 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 317704b Update to version 1.1.0; Fixes RHBZ#2242416