[Bug] Fix timestamp in temporary message (#369)

* [Bug] Fix timestamp in temporary message

* Fix tests

app/javascript/widget/store/modules/conversation.js

@@ -8,7 +8,7 @@ import DateHelper from '../../../shared/helpers/DateHelper';
 const groupBy = require('lodash.groupby');
 
 export const createTemporaryMessage = content => {
-  const timestamp = new Date().getTime();
+  const timestamp = new Date().getTime() / 1000;
   return {
     id: getUuid(),
     content,

app/javascript/widget/store/modules/specs/conversation/actions.spec.js

@@ -24,7 +24,7 @@ describe('#actions', () => {
         id: '1111',
         content: 'hello',
         status: 'in_progress',
-        created_at: 1466424490000,
+        created_at: 1466424490,
         message_type: 0,
       });
     });