$ git clone -n https://src.fedoraproject.org/rpms/rust-lzma-rust2.git /var/lib/mock/f45-build-43094-800/root/chroot_tmpdir/scmroot/rust-lzma-rust2
Cloning into '/var/lib/mock/f45-build-43094-800/root/chroot_tmpdir/scmroot/rust-lzma-rust2'...
$ git fetch origin 74bfc3dda146beaed22ba4dac5a83060eb790a28:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-lzma-rust2
 * [new ref]         74bfc3dda146beaed22ba4dac5a83060eb790a28 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 74bfc3d Update to version 0.20.1; Fixes RHBZ#2521569