def wf_webhook_id?(id)
      return true if id.is_a?(String) && id =~ /^[a-zA-Z0-9]{16}$/
      raise Wavefront::Exception::InvalidWebhookId
    end
def wf_webhook_id?(id)
      return true if id.is_a?(String) && id =~ /^[a-zA-Z0-9]{16}$/
      raise Wavefront::Exception::InvalidWebhookId
    end
Ensure the given argument is a valid webhook ID.

 @param id [String] webhook ID
 @return true if valid
 @raise Wavefront::Exceptions::InvalidWebhook if not valid