$ git clone -n https://src.fedoraproject.org/rpms/rust-chrono-tz-build.git /var/lib/mock/f42-build-side-1-3533556-46362/root/chroot_tmpdir/scmroot/rust-chrono-tz-build
Cloning into '/var/lib/mock/f42-build-side-1-3533556-46362/root/chroot_tmpdir/scmroot/rust-chrono-tz-build'...
$ git fetch origin fbfee689029faedb0a044669e776859ed1c2a92b:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-chrono-tz-build
 * [new ref]         fbfee689029faedb0a044669e776859ed1c2a92b -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at fbfee68 Update to version 0.4.1; Fixes RHBZ#2354504