$ git clone -n https://src.fedoraproject.org/rpms/rust-byte-unit.git /var/lib/mock/f38-build-side-43-rust-devel-1416857-31457/root/chroot_tmpdir/scmroot/rust-byte-unit
Cloning into '/var/lib/mock/f38-build-side-43-rust-devel-1416857-31457/root/chroot_tmpdir/scmroot/rust-byte-unit'...
$ git fetch origin 24b6cfc72c6e45368c20d7d070c13c950b7419cf:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-byte-unit
 * [new ref]         24b6cfc72c6e45368c20d7d070c13c950b7419cf -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 24b6cfc Update to version 4.0.19; Fixes RHBZ#2178368