message: Only run rustfmt on the stable channel
  This is what most developers will be using locally, and it avoids blocking the build if different rustfmt versions disagree.
diff: @@ -64,7 +64,7 @@ jobs:
  runs-on: ubuntu-20.04
  strategy:
  matrix:
  - rust: ["1.42.0", "stable", "beta", "nightly"]
  + rust: ["stable"]
  name: Rustfmt (${{ matrix.rust }})
  steps:
  - uses: actions/checkout@v2
  