feat: Add warnings to PineconeDocumentStore about indexing metadata if filters return no documents

[Namoush]

Related Issues

• fixes Pinecone: warn users about indexing metadata if filters return no documents #3031

Proposed Changes:

This pull request adds a warning for query_by_embedding and get_all_documents_generator in PineconeDocumentStore when a filter is used through an user action but no results are obtained. As it is referenced in this issue #3021, there's no way to know which metadata fields are indexed currently, so these warnings serve as a hint for users to revisit their queries in the circumstances referenced above (used a filter + no results obtained).

How did you test it?

query_by_embedding tested ✅(Edited Tutorial 1 with some help from this notebook here that was added as testing material in the PineconeDocumentStore implementation PR #2254
get_all_documents_generator tested ✅ through the upstream method get_all_documents

Notes for the reviewer

I have preemptively opened the pull request as it is encouraged in the CONTRIBUTING section.
I am still exploring the framework and this is my first os pull request so bear with me 😅.

Checklist

• I have read the contributors guidelines and the code of conduct
• I have updated the related issue with new insights and changes
• I added tests that demonstrate the correct behavior of the change
• I've used the conventional commit convention for my PR title
• I documented my code
• I ran pre-commit hooks and fixed any issue

[ZanSara]

Hello @Namoush! Thank you for this PR 🙂 There is a big PineconeDocumentStore refactoring by the Pinecone team being merged today, so I will hold this one up until it's done. There are probably going to be some conflicts, so keep an eye out for them.

[Namoush]

Thanks for merging main's changes into this branch + solving the conflicts @ZanSara . I did fix the if clause evaluations and manually tested both flows.

[ZanSara]

Hey @Namoush, I've merged main again as you stumbled upon a new pylint warning that prevented the CI from running. If the tests are all green I'm going to merge this PR today 🙂

[ZanSara]

Thank you!