Host-local reference PNGs for P20 same-renderer regression.

Generated by `make generate-parity-local` with this tree's
`rsvg-convert -d 72 -p 72` and `RSVG_PARITY=1` (P19 test fonts).

These are **not** the librsvg 2.62.3 oracle. The rust PNGs next to
the SVGs in `../parity/` stay the oracle for `make check-parity`.
`make check-parity-local` compares this renderer to itself.

Do not replace `../parity/*-ref.png`.
