Python 3.9 annotation compatibility (#16852)

* small fix, prevent annoying error log when registering keydown esc from user custom js

* Update script.js

Co-authored-by: missionfloyd <missionfloyd@users.noreply.github.com>

---------

Co-authored-by: missionfloyd <missionfloyd@users.noreply.github.com>

modules/util.py

@@ -1,3 +1,4 @@
+from __future__ import annotations
 import os
 import re
 

script.js

@@ -182,7 +182,7 @@ document.addEventListener('keydown', function(e) {
         const lightboxModal = document.querySelector('#lightboxModal');
         if (!globalPopup || globalPopup.style.display === 'none') {
             if (document.activeElement === lightboxModal) return;
-            if (interruptButton.style.display === 'block') {
+            if (interruptButton?.style.display === 'block') {
                 interruptButton.click();
                 e.preventDefault();
             }