Update index.md

adding last login info

Author: jplassnibatt

docs/api/index.md

@@ -1455,10 +1455,15 @@ Success response, with a list of users:
     "created": "2016-07-17T18:42:00Z",
     "updated": "2018-08-24T13:53:00Z",
     "lastJob": "2018-08-28T13:31:00Z",
-    "tokens": 6
+    "tokens": 6,
+    "lastLogin": "2025-09-08T13:29:21Z"
 }]
 ```
 
+**Since v53**
+
+* `lastLogin` Last login time for a user.
+
 **Since v27**:
 
 * `created` Creation date of the user.