Bug 1511312 - [fxui] Re-enable update permissions for update tests. r=ato

Differential Revision: https://phabricator.services.mozilla.com/D15641

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

testing/firefox-ui/harness/firefox_ui_harness/runners/update.py

@@ -13,6 +13,7 @@ from firefox_ui_harness.testcases import UpdateTestCase
 
 
 DEFAULT_PREFS = {
+    'app.update.disabledForTesting': False,
     # Bug 1355026: Re-enable when support for the new simplified UI update is available
     'app.update.doorhanger': False,
     'app.update.log': True,