Add & apply pre-commit and linting

[jwodder]

Part of #325.

[jwodder]

@yarikoptic Please merge this soon.

[jwodder]

@yarikoptic I expect there will be more PRs after this that will need to be merged quickly lest they create merge conflicts with other PRs created around the same time. How should this be handled?

[yarikoptic]

I would have left autogenerated files without changes -- not familiar yet with turtle format intricately but may be those space indentations are important part of the syntax...? I have tested this one (with trailing spaces removed) at some randomly found http://ttl.summerofcode.be/ -- seems to be ok. I think we can proceed but might need to be ready to revert this part of cleansing

[yarikoptic]

sorry for the delay. I left a comment, let's proceed

[yarikoptic]

@yarikoptic I expect there will be more PRs after this that will need to be merged quickly lest they create merge conflicts with other PRs created around the same time. How should this be handled?

I will keep an eye. Worse comes to worse, feel free to merge yourself, I will review later or just build up the chain of PRs basing one on top of another.

[github-actions]

🚀 PR was released in v4.0.0 🚀