DEV: prevents Firefox ESR tests to crash on `||=` (#14758)

DEV: prevents Firefox ESR tests to crash on ||= (#14758)

A follow up PR should investigate why proposal-logical-assignment-operators is not getting used here (test file?) but this should be enough to get things running.

diff --git a/app/assets/javascripts/discourse/tests/helpers/presence-pretender.js b/app/assets/javascripts/discourse/tests/helpers/presence-pretender.js
index 7afc731..991b3ad 100644
--- a/app/assets/javascripts/discourse/tests/helpers/presence-pretender.js
+++ b/app/assets/javascripts/discourse/tests/helpers/presence-pretender.js
@@ -35,8 +35,10 @@ export default function (helper) {
 }
 
 export function getChannelInfo(name) {
-  channels[name] ||= { count: 0, users: [], last_message_id: 0 };
-  return channels[name];
+  return (
+    channels[name] ||
+    (channels[name] = { count: 0, users: [], last_message_id: 0 })
+  );
 }
 
 export function joinChannel(name, user) {

GitHub sha: 9e19b22f64316b61f78e7f3d5b7af54e54eedf6c

This commit appears in #14758 which was approved by OsamaSayegh. It was merged by jjaffeux.