Add workflows for pre-commit and PyPI release

[martinhoyer]

The simple linting step uses the existing pre-commit config and https://github.com/pre-commit/action. The action could be replaced with https://pre-commit.ci/, as needed.

Release step uses the reference setup from https://docs.pypi.org/trusted-publishers/.
It would be trigger once release is created here on github.

[martinhoyer]

I'm thinking we might want to add

  workflow_dispatch:
    inputs:
      ref:
        description: 'Tag to release'
        required: true

to the publish step, to make sure each release is tagged (otherwise the package version would be invalid).

Or do you think it's redundant and no-one would create a release without a tag anyway?

[martinhoyer]

Sneaking in a fix for an issue introduced while refactoring, where the shell would exit on errors like "Command not found"