anchor.diff:  
   PUT my-data-stream/_bulk?pipeline=my-pipeline
   { "create":{ } }
  -{ "@timestamp": "2099-03-08T11:04:05.000Z", "my-keyword-field": "foo" }
  +{ "@timestamp": "2099-03-07T11:04:06.000Z", "my-keyword-field": "foo" }
   { "create":{ } }
  -{ "@timestamp": "2099-03-08T11:06:07.000Z", "my-keyword-field": "bar" }
  +{ "@timestamp": "2099-03-07T11:04:07.000Z", "my-keyword-field": "bar" }
   ----
   
   You can also use the `pipeline` parameter with the <<docs-update-by-query,update
  
positive.code:           "my-keyword-field": "bar"
          },
          "_ingest": {
            "timestamp": "2099-02-30T22:30:03.188Z"
          }
        }
      }
    ]
  }
  ----
  // TESTRESPONSE[s/"2099-02-30T22:30:03.187Z"/$body.docs.0.doc._ingest.timestamp/]
  // TESTRESPONSE[s/"2099-02-30T22:30:03.188Z"/$body.docs.1.doc._ingest.timestamp/]
  
  [discrete]
  [[add-pipeline-to-indexing-request]]
  
negative.code:           "my-keyword-field": "foo"
          },
          "_ingest": {
            "timestamp": "2099-03-07T11:04:03.000Z"
          }
        }
      },
  