Website request: Remove receive-from-zoom webhook.

[eashaw]

Issue/Goal:

Remove the Zoom revenue accelerator integration from the website.

How?

• Delete the receive-from-zoom webhook, update routes and policies.
• Remove the configuration variables used by the webhook
• Deactivate the custom integration in Zoom.

[fleet-release]

Zoom webhook leaves,
Routes updated, variables freed,
Web's tranquility achieved.