$ git clone -n https://src.fedoraproject.org/rpms/rust-group.git /var/lib/mock/f45-build-42148-791/root/chroot_tmpdir/scmroot/rust-group
Cloning into '/var/lib/mock/f45-build-42148-791/root/chroot_tmpdir/scmroot/rust-group'...
$ git fetch origin 075b00cbf5975caf6b1701e72fe80da98b74c672:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-group
 * [new ref]         075b00cbf5975caf6b1701e72fe80da98b74c672 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 075b00c Update to version 0.14.0; Fixes RHBZ#2483860