$ git clone -n https://src.fedoraproject.org/rpms/rust-image.git /var/lib/mock/f42-build-side-111044-59206094-6571867/root/chroot_tmpdir/scmroot/rust-image
Cloning into '/var/lib/mock/f42-build-side-111044-59206094-6571867/root/chroot_tmpdir/scmroot/rust-image'...
$ git fetch origin 5f347bd14606d8bae91d38fca7f83506214861f1:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-image
 * [new ref]         5f347bd14606d8bae91d38fca7f83506214861f1 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 5f347bd Update to version 0.25.6; Fixes RHBZ#2354763