anchor.diff:  }
   --------------------------------------------------
   // TEST[skip:setup:server_metrics_datafeed]
  +
   
   When the {dfeed} is updated, you receive the full {dfeed} configuration with
   with the updated values:
  
positive.code:   (Optional, array) An array of index names. Wildcards are supported. For
    example: `["it_ops_metrics", "server*"]`.
  
  `job_id`::
   (Optional, string) A numerical character string that uniquely identifies the
   {anomaly-job}.
  
  `query`::
    (Optional, object) The {es} query domain-specific language (DSL). This value
    corresponds to the query object in an {es} search POST body. All the options
    that are supported by {es} can be used, as this object is passed verbatim to
    {es}. By default, this property has the following value:
    `{"match_all": {"boost": 1}}`.
  
  `query_delay`::
    (Optional, <<time-units, time units>>) The number of seconds behind real-time 
  
negative.code: cluster privileges to use this API. See
  {stack-ov}/security-privileges.html[Security privileges].
  
  
  [[ml-update-datafeed-desc]]
  ==== {api-description-title}
  
  If you update a {datafeed} property, you must stop and start the {dfeed} for the 
  change to be applied.
  
  IMPORTANT: When {es} {security-features} are enabled, your {dfeed} remembers
  which roles the user who updated it had at the time of update and runs the query
  