$ git clone -n https://src.fedoraproject.org/rpms/rust-thin-vec.git /var/lib/mock/f45-build-45457-823/root/chroot_tmpdir/scmroot/rust-thin-vec
Cloning into '/var/lib/mock/f45-build-45457-823/root/chroot_tmpdir/scmroot/rust-thin-vec'...
$ git fetch origin 2bb9489b7d560273c5106028cd79cc2706de4579:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-thin-vec
 * [new ref]         2bb9489b7d560273c5106028cd79cc2706de4579 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 2bb9489 Update to version 0.2.19