Check all languages against latest source strings

[m-aciek]

Closes #2. Dependent on https://git.afpy.org/AFPy/potodo/pulls/11.

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📚 Preview 📚: https://pydocs-translation-dashboard.readthedocs.io/check-against-latest/

[rffontenelle]

The percentages are different that I expected. For instance, pt_BR 3.13 was 63% and zh_CN was 93% (matching Transifex stats), but now they are 53 and 73%)

UPDATE: Got it, that's the whatsnew/changelog.pot adding 12K strings to the math ...

[m-aciek]

I don't know a way to install gettext on Read the Docs without a sudo. Not sure, maybe we should switch to lightweight PR preview, like https://github.com/marketplace/actions/deploy-pr-preview?

[rffontenelle]

I don't think you can install using sudo in build.commands. Normally you would use build.apt_packages (see https://github.com/sphinx-doc/sphinx-doc-translations/blob/master/.readthedocs.yml#L7-L8), but AFAIK the environment of build.commands ignores such command.

See readthedocs/readthedocs.org#9599

[m-aciek]

Read the Docs build is working after suggested changes 🎉