XML RPC request should get hard blocker quicker (#8855)

Currently math fallback doesn't do anything for xml rpc requests.

This PR blocks xmlrpc requests for would regularly show the math test just gets bypassed and allows more valid xml rpc requests though.

modules/protect.php

@@ -554,7 +554,7 @@ function block_with_math() {
 		 * @param bool true Should we fallback to the Math questions when an IP is blocked. Default to true.
 		 */
 		$allow_math_fallback_on_fail = apply_filters( 'jpp_use_captcha_when_blocked', true );
-		if ( ! $allow_math_fallback_on_fail ) {
+		if ( ! $allow_math_fallback_on_fail || Jetpack_Constants::is_true( 'XMLRPC_REQUEST' ) ) {
 			$this->kill_login();
 		}
 		include_once dirname( __FILE__ ) . '/protect/math-fallback.php';