Fixes a bug in which nested subdags were not passed required

[elijahbenizzy]

configuration parameters

We're aggressive in pruning parameters we pass to decorators, so they don't use everything. SubDAGs didn't declare them, as they only know the configurations required once they parse the function that they decorate, as well as import the subdags they use.

Rather than the more correct, but more complicated fix, this utilizes the "out" -- allowing required_config to return None so everything gets passed in. We need to think about the best way to do this, but for now this is little harm and we can walk it back -- the contract is solid.

[Short description explaining the high-level reason for the pull request]

Changes

How I tested this

Notes

Checklist

• PR has an informative and human-readable title (this will be pulled into the release notes)
• Changes are limited to a single goal (no scope creep)
• Code passed the pre-commit check & code is left cleaner/nicer than when first encountered.
• Any change in functionality is tested
• New functions are documented (with a description, list of inputs, and expected output)
• Placeholder code is flagged / future TODOs are captured in comments
• Project documentation has been updated if adding/changing functionality.