updated timestamp format to ISO in realtime payload

app/views/docs/realtime.phtml

@@ -405,10 +405,10 @@ subscription.close()</code></pre>
                 timestamp
             </td>
             <td data-title="Type: ">
-                integer
+                string
             </td>
             <td data-title="Description: ">
-                The <a href="https://en.wikipedia.org/wiki/Unix_time" rel="noopener" target="_blank">UNIX timestamp</a> from the server to ensure consistency across all client platforms and real-time technologies.
+                The <a href="https://en.wikipedia.org/wiki/ISO_8601" rel="noopener" target="_blank">ISO 8601 timestamp</a> in UTC timezone from the server to ensure consistency across all client platforms and real-time technologies.
             </td>
         </tr>
         <tr>
@@ -448,7 +448,7 @@ subscription.close()</code></pre>
         "collections.user.documents",
         "collections.user.documents.627a95c0785cc5c7fff2"
     ],
-    "timestamp": 1653957271,
+    "timestamp": "2022-10-17T07:29:37+00:00",
     "payload": {
         "field1": "lorem ipsum",
         "field2": [],
@@ -532,4 +532,4 @@ client.setEndpointRealtime("[HOSTNAME_OR_IP]")</code></pre>
 <p>The SDK creates a single WebSocket connection for all subscribed channels. Each time a channel is added or unsubscribed - the SDK currently creates a completely new connection and terminates the old one. Therefore, subscriptions to channels should always be done in conjunction with state management so as not to be unnecessarily built up several times by multiple components' life cycles.</p>
 
 <h3>Server-Side?</h3>
-<p>We currently are not offering access to realtime with Server SDKs and an API key.</p>
+<p>We currently are not offering access to realtime with Server SDKs and an API key.</p>