$ git clone -n https://src.fedoraproject.org/rpms/rust-tokio.git /var/lib/mock/f41-build-1187673-22141/root/chroot_tmpdir/scmroot/rust-tokio
Cloning into '/var/lib/mock/f41-build-1187673-22141/root/chroot_tmpdir/scmroot/rust-tokio'...
$ git fetch origin e2f716b34d0ea87ef1931c3b4c310baa02f8ba4e:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-tokio
 * [new ref]         e2f716b34d0ea87ef1931c3b4c310baa02f8ba4e -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at e2f716b Update to version 1.38.0; Fixes RHBZ#2284043