Add ADDITIONAL_PYTHON_DEPS

[wittfabian]

Description

Since we have separate "build" segment for the production image, We will need to add any extra dependencies there rather than on top of the base image if someone wants to add those dependencies.

Reference: #8604

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[boring-cyborg]

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[potiuk]

Nice!. I will also add an option to extend Breeze with that option - but that can be done separately.

[potiuk]

You can mark it as ready for review to merge it @wittfabian - or you might try to extend Breeze with an option to add --additional-python-deps flag if you are brave enough :)

[wittfabian]

I have not yet worked with Breeze, but I would like to see the result ;)
I am already working on #8866.

[wittfabian]

@potiuk Must the flag be added here?
https://github.com/apache/airflow/blob/master/breeze#L770

[potiuk]

There are a few places - breeze-complete and breeze are the two scripts. You can just search for another flag and do it similarly, or I can add it later after your PRs are merged and cc: you in the PR.

[boring-cyborg]

Awesome work, congrats on your first merged pull request!