$ git clone -n https://src.fedoraproject.org/rpms/rust-whoami.git /var/lib/mock/f41-build-59237924-6572177/root/chroot_tmpdir/scmroot/rust-whoami
Cloning into '/var/lib/mock/f41-build-59237924-6572177/root/chroot_tmpdir/scmroot/rust-whoami'...
$ git fetch origin 5ff9ab0f07f30d45cf5c76e7fa19f854f0eb34e8:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-whoami
 * [new ref]         5ff9ab0f07f30d45cf5c76e7fa19f854f0eb34e8 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 5ff9ab0 Update to version 1.6.0; Fixes RHBZ#2354376