Goldens updated due to Skia AA changes. We previously also made a mistake by having a golden test run on MacOS.

git log 3ffa36295234..50c2e69da --no-merges --oneline
50c2e69da Roll src/third_party/skia 1b62fad4b188..b27a9cf2f4a8 (1 commits) (flutter/engine#6514)
8757bf2a1 Roll src/third_party/skia 05caa69a3f5a..1b62fad4b188 (2 commits) (flutter/engine#6513)
c2fd10ad1 Roll src/third_party/skia 2a138544646d..05caa69a3f5a (1 commits) (flutter/engine#6512)