MDL-40245 assignment: download all submissions raise time limit

mod/assign/locallib.php

@@ -2618,6 +2618,9 @@ class assign {
         // More efficient to load this here.
         require_once($CFG->libdir.'/filelib.php');
 
+        // Increase the server timeout to handle the creation and sending of large zip files.
+        core_php_time_limit::raise();
+
         $this->require_view_grades();
 
         // Load all users with submit.