feat: Add support for pinecone index host url

[shazy792]

Adding support for pinecone index host url to target indices as recommended by pinecone for production uses cases
Pinecone docs ref: https://docs.pinecone.io/guides/data/target-an-index

Checklist (if applicable):

• PR title is following https://www.conventionalcommits.org/en/v1.0.0/
• Docs updated (updated docs or a docs bug required)

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