Bug 1498862 - Increase access limit for chrome.override_package.global to 70 to prevent failures for 64 beta r=johannh

Differential Revision: https://phabricator.services.mozilla.com/D8696

--HG--
extra : moz-landing-system : lando

browser/base/content/test/performance/browser_preferences_usage.js

@@ -101,6 +101,10 @@ add_task(async function startup() {
       min: 5,
       max: 55,
     },
+    "chrome.override_package.global": {
+      min: 0,
+      max: 50,
+    },
   };
 
   let startupRecorder = Cc["@mozilla.org/test/startuprecorder;1"].getService().wrappedJSObject;