chore: fix flaky test (#3928)

* logOut is async so handle with a promise

spec/ParseUser.spec.js

@@ -1204,7 +1204,7 @@ describe('Parse.User testing', () => {
         strictEqual(provider.authData.expiration_date, provider.synchronizedExpiration);
         ok(model._isLinked("facebook"), "User should be linked to facebook");
 
-        Parse.User.logOut();
+        Parse.User.logOut().then(() => {
           ok(provider.loggedOut);
           provider.loggedOut = false;
 
@@ -1227,6 +1227,7 @@ describe('Parse.User testing', () => {
               done();
             }
           });
+        }, done.fail);
       },
       error: function(model, error) {
         jfail(error);