gpasc-draft-groups-by-page.php: Fixed issue where snippet used non-standard function to check for AJAX requests.

Author: spivurno

gp-advanced-save-and-continue/gpasc-draft-groups-by-page.php

@@ -11,7 +11,7 @@
 	// Set ignore parameters to false if you would like parameters to be included in identifying unique pages.
 	$ignore_parameters = true;
 
-	if ( is_ajax() ) {
+	if ( wp_doing_ajax() ) {
 		return $tokens;
 	}