Updating the contact source value for webinars and gated docs to match
the new sfdc values
<!-- This is an auto-generated comment: release notes by coderabbit.ai
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## Summary by CodeRabbit
* **Bug Fixes**
* Corrected CRM contact-source classification so webinar access requests
and whitepaper downloads are categorized separately from general contact
form submissions.
* **Chores**
* Expanded accepted contact-source values in the CRM integration to
include distinct labels for webinars and gated documents.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->
johnjeremiah
087ba3ff80