$ git clone -n https://src.fedoraproject.org/rpms/rust-dirs-sys.git /var/lib/mock/f38-build-side-43-rust-devel-1410790-31421/root/chroot_tmpdir/scmroot/rust-dirs-sys
Cloning into '/var/lib/mock/f38-build-side-43-rust-devel-1410790-31421/root/chroot_tmpdir/scmroot/rust-dirs-sys'...
$ git fetch origin 858b3d806e3ce481052c8821f4bda05cf584a7e8:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-dirs-sys
 * [new ref]         858b3d806e3ce481052c8821f4bda05cf584a7e8 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 858b3d8 Update to version 0.4.1; Fixes RHBZ#2175300