Send success only IF HelpScout ticket was created?

[helgatheviking]

Currently we send a success header if there's any action hook attached.... which there always is one set for the current API chosen in the settings. Instead, can we look at all at whether the ticket is actually handled successfully? Also we always return a -1 result... which isn't super handy when debuggin via postman. note to future self.

SendGrid payload needs adjusting to

	/**
	 * Get the webhook payload.
	 *
	 * @return  array - the $_POSTed data.
	 */
	public function get_payload() {

	    $payload = [];

        $payload_json = @file_get_contents('php://input');
        
        if ( !empty($payload_json ) ) {
            $payload = json_decode($payload_json, true);
        } elseif ( ! empty( $_POST ) ) {
            $payload = $_POST;
        }

	    return $payload;
		
	}

when testing via postman