Fix tasks.json

Two of my previous CLs stepped on each other.

BUG=skia:

Change-Id: I53d49f283e466ad7fd6c38a6d4243c084dd324c7
Reviewed-on: https://skia-review.googlesource.com/5519
Reviewed-by: Eric Boren <borenet@google.com>
tree: e8604bbe4f17137f2d314043625d90e42c5d7323
  1. recipe_modules/
  2. recipes.py
  3. recipes/