[Autoroller] Remove mac retina from freetype-chromium
[Autoroller] Remove mac retina from freetype-chromium

Remove luci.chromium.try:mac10.13_retina-blink-rel from the
freetype-chromium roller trybots since it doesn't seem to exist anymore.

Change-Id: I72c0f8821a6e472b0666d351d4ffbb052a2e2816
Reviewed-on: https://skia-review.googlesource.com/c/buildbot/+/312817
Reviewed-by: Eric Boren <0e499112533c8544f0505ea0d08394fb5ad7d8fa@google.com>
Commit-Queue: Ben Wagner <53965154ffeecc4a10886eab9259e95965f2979a@google.com>

google/skia-buildbot,google/skia-buildbot,google/skia-buildbot,google/skia-buildbot,google/skia-buildbot,google/skia-buildbot,google/skia-buildbot,google/skia-buildbot