Add pybabel tasks to the build hook

[goessebr]

The .mo files are now checked into the GitHub repository. However, we could consider leaving them out of the repository.

When building a wheel, we want to ensure that the .mo files are present, so we need to add the pybabel commands to the build hook. The commands can be found in the documentation: Frontend Development.

For local development, pip install -e . will trigger the build hook and ensure updated .mo files.

I don't think we need additional documentation. The pybabel compile command in the General Installation section should be sufficient to have translations present when developing this project.

Scope

• remove mo files out of github
• add mo files to gitginore
• add pybabel tasks to build hook