post
https://services.fountain.com/api/servicemessaging/processes/webhooks/webhookCustomHeaderValue
Encrypt a custom header value for a webhook.
Validates and encrypts a custom HTTP header value for a webhook. Store the returned encryptedValue on the webhook's configuration.customHeaders entry; the clear-text value is never persisted and cannot be retrieved afterwards. Header names must follow HTTP naming rules and cannot be a header Fountain already sets (Content-Type, Accept, X-Fountain-*, and transport headers).