fix(agenda): Handle .html agenda suffix in Vue router (#4589)

client/router.js

@@ -23,6 +23,12 @@ export default createRouter({
       }
     },
     // -> Redirects
+    {
+      path: '/meeting/:meetingNumber(\\d+)?/agenda.html',
+      redirect: to => {
+        return { name: 'agenda' }
+      }
+    },
     {
       path: '/meeting/:meetingNumber(\\d+)?/agenda/personalize',
       redirect: to => {