Always retry Navigation tests (live github.com can be slow anywhere)

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: richardkmichael

tests/firefox/extension.spec.js

@@ -408,7 +408,7 @@ describe('Options', function () {
 
 describe('Navigation', function () {
   this.timeout(30000);
-  this.retries(process.env.CI ? 2 : 0);
+  this.retries(2);
 
   const bookmarkSelector = '[data-extension-bookmark]';
   const headerActionsSelector = '[data-component="PH_Actions"]';