The current HTTP Webhook sink only supports custom JWT authentication.

Implementing the Standard Webhooks protocol can make it easier for users to consume the webhooks and offers additional protection agains SSRF, spoofing, and replay attacks.

https://www.standardwebhooks.com/

The Standard Webhooks specification is a set of conventions to be followed by webhook producers (senders) to provide webhook consumers (receivers) a secure, consistent, and interoperable interface for webhooks.