[canvaskit] Fix red_line.skp test

Change-Id: I7c9610faf56af21fff17d1bfd96297770defb951
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/430857
Auto-Submit: Kevin Lubick <kjlubick@google.com>
Reviewed-by: Mike Reed <reed@google.com>
Commit-Queue: Mike Reed <reed@google.com>
2 files changed