Add pre-commit checks and auto fixes

Code style checks are now automatically performed when committing to the local repository, so issues can be detected before running a CI pipeline. Checks are performed using the pre-commit tool which runs a few integrated checks as well as Prettier and Stylelint. Futhermore, auto fixes are applied when possible.

pre-commit is a Python-based tool, which is automatically installed with a postinstall script using pip. Python and pip need to be installed manually.

If the git hook needs to be removed for whatever reason, pre-commit uninstall can be run to handle this.

Related: particify/dev/common-concerns#45