$ git clone -n https://src.fedoraproject.org/rpms/rust-yaml-rust0.3.git /var/lib/mock/f45-build-46234-832/root/chroot_tmpdir/scmroot/rust-yaml-rust0.3
Cloning into '/var/lib/mock/f45-build-46234-832/root/chroot_tmpdir/scmroot/rust-yaml-rust0.3'...
$ git fetch origin 6fcd04c33cd066dfc8da7610b94aa7beca13abe3:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-yaml-rust0.3
 * [new ref]         6fcd04c33cd066dfc8da7610b94aa7beca13abe3 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 6fcd04c Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild