Currently, the token-based authentication method for the webhooks connector requires a header named "X-Fivetran-Secret-Token" to be included with each incoming webhook payload. It would be nice to have an option to specify a custom authentication header for a connector to use in place of Fivetran's default authentication header. This would allow webhook connectors to authenticate payloads from applications that use a different name for their authentication header, which is necessary for applications where customers do not have direct control over how webhook payloads are sent.