[BUG] Operation-type is not transformed about opensearch-benchmark HOT 2 CLOSED

{
  "_index": "benchmark-metrics-2023-05",
  "_id": "CcSTNYgBe89sZjg205DG",
  "_version": 1,
  "_score": null,
  "_source": {
    "@timestamp": 1684526059367,
    "relative-time-ms": 33.14203800000026,
    "test-execution-id": "3e240d18-fc87-4c49-9712-863196efcef4",
    "test-execution-timestamp": "20230519T195412Z",
    "environment": "local",
    "workload": "geonames",
    "test_procedure": "append-no-conflicts",
    "provision-config-instance": "external",
    "name": "latency",
    "value": 671.8102729999993,
    "unit": "ms",
    "sample-type": "normal",
    "meta": {
      "source_revision": "unknown",
      "distribution_version": "1.1.0",
      "distribution_flavor": "oss",
      "success": true
    },
    "task": "create-index",
    "operation": "create-index",
    "operation-type": "create-index"
  },
  "fields": {
    "@timestamp": [
      "2023-05-19T19:54:19.367Z"
    ],
    "test-execution-timestamp": [
      "2023-05-19T19:54:12.000Z"
    ]
  },
  "sort": [
    1684526052000
  ]
}