add support for autoformatting via pre-commit.ci

[BenWibking]

The pre-commit.ci hosted CI service will run clang-format automatically on PRs if they do not already match the formatting style. This should prevent having to manually run the formatting bot (which doesn't appear to work with forks).

Despite its name, it does not actually require installing pre-commit hooks at all. It just autoformats PRs by running the same tools that would be run during a pre-commit step locally.

[tbhaxor]

I can work on this. Recently I configured pre-commit.ci for one of my repository that does linting and formatting on python files.

[tbhaxor]

Could you assign it to me?

[Yurlungur]

We discussed this on the previous parthenon call. We were not confident we want to switch to this yet. We're still evaluating.

[tbhaxor]

Hi @Yurlungur Thanks for the update. Is it a public meeting where I can join too?

[tbhaxor]

@Yurlungur Ping

[Yurlungur]

@tbhaxor sorry for the delay. We have bi-weekly calls, which are currently for developers/maintainers heavily invested in the code and not public. As the project grows, this will probably change.

If you're interested in getting more involved in the project, why not join our matrix channel (which is like slack but more privacy first)? There are often lively discussions there.

You might also introduce yourself a bit---what's your background? Why are you interested in Parthenon/AthenaPK and what do you hope to do with the code? Personally I'm quite appreciative of the work you've put in to contribute to the project, but I am a bit surprised. Parthenon/AthenaPK are pretty specialized science tools, and the communities they serve are pretty small. It's unusual for someone we don't know to contribute out of the blue. I've added a new pinned issue, #862 for this purpose.