Tests: Fixed listeners_spec.js (DST)

closes #9188

- make timezone offsets dynamic, yey!

core/test/integration/model/base/listeners_spec.js

@@ -1,8 +1,8 @@
 /*jshint unused:false*/
 var should = require('should'),
     Promise = require('bluebird'),
-    moment = require('moment'),
     sinon = require('sinon'),
+    moment = require('moment-timezone'),
     rewire = require('rewire'),
     _ = require('lodash'),
     config = require('../../../../server/config'),
@@ -156,7 +156,7 @@ describe('Models: listeners', function () {
                  * The post should be still scheduled for 8PM UTC time.
                  * So the database UTC string must be 2017-04-19 20:00:00.
                  */
-                scope.timezoneOffset = 180;
+                scope.timezoneOffset = moment.tz.zone('Etc/UTC').offset(now) - moment.tz.zone('Asia/Baghdad').offset(now);
                 scope.oldTimezone = 'Asia/Baghdad';
                 scope.newTimezone = 'Etc/UTC';
 
@@ -213,7 +213,7 @@ describe('Models: listeners', function () {
                  * The post should be still scheduled for 8PM UTC time.
                  * So the database UTC string must be 2017-04-18 11:00:00.
                  */
-                scope.timezoneOffset = -420;
+                scope.timezoneOffset = moment.tz.zone('Asia/Seoul').offset(now) - moment.tz.zone('Europe/Amsterdam').offset(now);
                 scope.oldTimezone = 'Europe/Amsterdam';
                 scope.newTimezone = 'Asia/Seoul';
 
@@ -278,7 +278,7 @@ describe('Models: listeners', function () {
                         });
                 });
 
-                scope.timezoneOffset = -180;
+                scope.timezoneOffset = moment.tz.zone('Asia/Baghdad').offset(now) - moment.tz.zone('Etc/UTC').offset(now);
                 scope.oldTimezone = 'Asia/Baghdad';
                 scope.newTimezone = 'Etc/UTC';