$ git clone -n https://src.fedoraproject.org/rpms/rust-tokio.git /var/lib/mock/f42-build-side-1-3588973-46952/root/chroot_tmpdir/scmroot/rust-tokio
Cloning into '/var/lib/mock/f42-build-side-1-3588973-46952/root/chroot_tmpdir/scmroot/rust-tokio'...
$ git fetch origin ed891df52933fedc353d0206ad3bcce3ad6777e1:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-tokio
 * [new ref]         ed891df52933fedc353d0206ad3bcce3ad6777e1 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at ed891df Update to version 1.46.1; Fixes RHBZ#2375874