docs(salesforce): add missing salesforce source to cli doc

[remisalmon]

Checklist

• The PR conforms to DataHub's Contributing Guideline (particularly Commit Message Format)
• Links to related issues (if applicable)
• Tests for the changes have been added/updated (if applicable)
• Docs related to the changes have been added/updated (if applicable). If a new feature has been added a Usage Guide has been added for the same.
• For any breaking change/potential downtime/deprecation/big changes an entry has been made in Updating DataHub

This is adding the pip requirement for the salesforce ingestion source described here https://datahubproject.io/docs/generated/ingestion/sources/salesforce#integration-details (simple-salesforce) to the cli doc.

I tested locally that pip install acryl-datahub does not install simple-salesforce, but pip install acryl-datahub[salesforce] does.

[hsheth2]

Thanks - honestly this entire table probably should be autogenerated