$ git clone -n https://src.fedoraproject.org/rpms/rust-chrono.git /var/lib/mock/f40-build-2571413-62241/root/chroot_tmpdir/scmroot/rust-chrono
Cloning into '/var/lib/mock/f40-build-2571413-62241/root/chroot_tmpdir/scmroot/rust-chrono'...
$ git fetch origin 3179522af6ef9908d418aabc1a57396779439d7f:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-chrono
 * [new ref]         3179522af6ef9908d418aabc1a57396779439d7f -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 3179522 Update to version 0.4.35; Fixes RHBZ#2268172