$ git clone -n https://src.fedoraproject.org/rpms/rust-home.git /var/lib/mock/f40-build-2250772-54082/root/chroot_tmpdir/scmroot/rust-home
Cloning into '/var/lib/mock/f40-build-2250772-54082/root/chroot_tmpdir/scmroot/rust-home'...
$ git fetch origin 1a371b21ae94593c5d471f633ca01a8270869693:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-home
 * [new ref]         1a371b21ae94593c5d471f633ca01a8270869693 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 1a371b2 Update to version 0.5.9; Fixes RHBZ#2254774