Astra DB: explicit projection when reading from Astra DB

[hemidactylus]

In view of upcoming changes in the Astra DB Data API, this PR explicitly sets a projection every time a find command (or equivalent) is executed, in order to ensure all necessary fields of the document are returned by the API.

This occurs in the two method calls find_one and vector_find in the test test-ingest-astra-output.py.

With this change, future versions of the Data API, which may implement an exclude-vector-by-default policy, will not cause any disruption in these tests.

[potter-potter]

@hemidactylus Are there any code changes in the unstructured package needed for this? Or is it just in that test script that we are using to check our results?

If it is just this change, I will add to a current Unstructured PR. (easier to merge in that way)

#3003

[hemidactylus]

Hi, @potter-potter, it is just the test script indeed. Please feel free to close this and apply the patch within another PR :)
... and thank you for taking care of it!

[potter-potter]

Closing.
update added here:
#3003