Move clang-format outside the sanity check

[gabrieldemarmiesse]

Linked to #991

Uses: https://github.com/DoozyX/clang-format-lint-action

The check runs in 20s but we need to upgrade the clang format version. We're using 3.8 but the stable version is 10 now. The github action that we're using supports version 5 to 9.

I propose we bit the bullet now and bump the clang format version to 9.

Instructions to install clang-format-9:

wget -O - https://apt.llvm.org/llvm-snapshot.gpg.key | sudo apt-key add -
sudo add-apt-repository -u 'http://apt.llvm.org/bionic/ llvm-toolchain-bionic-9 main'
sudo apt install clang-format-9

format all with:

clang-format-9 -i --style=google **/*.cc **/*.h

The github action didn't support google style out of the box.
See DoozyX/clang-format-lint-action#3

I made a pull request for it: See DoozyX/clang-format-lint-action#5
and currently In the github file, I use a commit on my branch.

[gabrieldemarmiesse]

This pull request is ready for review

[WindQAQ]

Nice cleanup! I would suggest also modify CONTRIBUTING.md so that developers know how to format cpp codes (as make code-format won't format cpp codes after this change). Thank you.

[gabrieldemarmiesse]

@WindQAQ done

[WindQAQ]

Thanks.