fix(langchain): use correct class names for pinecone vectorstore check

[Yun-Kim]

Backports #9759 to 2.10.

This PR fixes the class names used to check for Pinecone vectorstore instances in the langchain integration. Previously the incorrect base class for all vectorstores was being used, which would mean all vectorstores would return true for this check.

Langchain has a tricky versioning system with tons of deprecations and removals (even between minor versions):

• langchain<0.1: Uses the base langchain module to access langchain.vectorstores.Pinecone (note this indirectly imports from langchain_community.
• langchain>=0.1: Uses the langchain_community module to access langchain_community.vectorstores.Pinecone
• langchain>=0.1 but if users have langchain-pinecone installed: Uses langchain_pinecone module to access
  langchain_pinecone.vectorstores.Pinecone (deprecated, subclass of PineconeVectorStore) or
  langchain_pinecone.vectorstores.PineconeVectorStore.

We use the above information to use as the logic to check if an instance is a pinecone vectorstore.

Checklist

• PR author has checked that all the criteria below are met
• The PR description includes an overview of the change
• The PR description articulates the motivation for the change
• The change includes tests OR the PR description describes a testing strategy
• The PR description notes risks associated with the change, if any
• Newly-added code is easy to change
• The change follows the library release note guidelines
• The change includes or references documentation updates if necessary
• Backport labels are set (if applicable)

Reviewer Checklist

• Reviewer has checked that all the criteria below are met
• Title is accurate
• All changes are related to the pull request's stated goal
• Avoids breaking API changes
• Testing strategy adequately addresses listed risks
• Newly-added code is easy to change
• Release note makes sense to a user of the library
• If necessary, author has acknowledged and discussed the performance implications of this PR as reported in the benchmarks PR comment
• Backport labels are set in a manner that is consistent with the release branch maintenance policy

[datadog-dd-trace-py-rkomorn]

Datadog Report

Branch report: yunkim/backport-9759-to-210
Commit report: ad8949c
Test service: dd-trace-py

✅ 0 Failed, 175422 Passed, 1904 Skipped, 12h 12m 16.76s Total duration (4m 54.61s time saved)

[pr-commenter]

Benchmarks

Benchmark execution time: 2024-07-25 18:12:59

Comparing candidate commit ad8949c in PR branch yunkim/backport-9759-to-210 with baseline commit 7e39ec5 in branch 2.10.

Found 0 performance improvements and 0 performance regressions! Performance is the same for 209 metrics, 9 unstable metrics.