Possible unnecessary code in `ci.yml`

[mhucka]

The CI workflow file ci.yml contains the following in the build job:

    - name: Install clang-format (Linux)
      if: runner.os == 'Linux'
      run: |
        sudo apt-get update
        sudo apt-get install -y clang-format

    - name: Install clang-format (macOS)
      if: runner.os == 'macOS'
      run: |
        brew install clang-format

However,

1. The job never runs clang-format – it only installs it
2. The only other job it runs is bazel test src/..., and I can't find evidence in the WORKSPACE or BUILD files that clang-format is invoked from them

It's possible clang-format is needed in a dependency, but just in case this was a left-over in the CI file from something else, I wanted to flag it.