pwa: add application icon to cache (#29361)

combo/apps/pwa/templates/combo/service-worker.js

@@ -1,4 +1,4 @@
-{% load combo gadjo %}
+{% load combo gadjo static %}
 
 /* global self, caches, fetch, URL, Response */
 'use strict';
@@ -25,7 +25,8 @@ function urlB64ToUint8Array(base64String) {
 var config = {
   version: 'v{{ version }}',
   staticCacheItems: [
-    '/__pwa__/offline/'
+    '/__pwa__/offline/',
+    '{% static "" %}{{ css_variant }}/{{ icon_prefix }}{{icon_sizes|last}}px.png'
   ],
   cachePathPattern: /^\/static\/.*/,
   handleFetchPathPattern: /.*/,