Removed duplicated line

Author: c8y3

docs/api_reference/reference/iris.v2.1.0.yaml

@@ -143,7 +143,6 @@ info:
     * Deprecated POST /manage/customers/delete/{customer_id}
     * Deprecated POST /global/tasks/add
     * Deprecated POST /global/tasks/update/{task_id}
-    * Deprecated POST /global/tasks/update/{task_id}
     * Deprecated POST /global/tasks/delete/{task_id}
     * Added documentation of missing GET /manage/severities/list
     * Added documentation of missing GET /manage/tlp/list