Add warning for community integration of document loaders

[Yacklin Wong (Yacklin)]

Overview

Just noticed that some users used community document loaders and complained a little bit. Add warning to reduce such complaints

Type of change

Type: Update existing documentation

Related issues/PRs

• GitHub issue: [langchain]: YoutubeLoaderDL integration is using the old import langchain.document_loaders #3883
• Feature PR:

Checklist

• I have read the contributing guidelines, including the language policy
• I have tested my changes locally using docs dev
• All code examples have been tested and work correctly
• I have used root relative paths for internal links
• I have updated navigation in src/docs.json if needed

[github-actions]

Thanks for opening a docs PR, Yacklin Wong (@Yacklin)! When it's ready for review, please add the relevant reviewers:

• @mdrxy (Python integrations)

[Yacklin Wong (Yacklin)]

Naomi Pentrel (@npentrel) quick fix