WIP Try to diagnose test failure on ES 7.10

[codefromthecrypt]

@xeraa The note about deprecation was valid, but actually the test fails, which is something I didn't raise a PR on before as was out of time..

Here's an http trace of the failing test which is related to composable templates. If you run this with environment ES_DEBUG=true you would see what I do ideally, but anyway maybe you can look and see what is wrong or if another http command in the test would make what is wrong easier to know.
httptrace.txt

Here's the actual /_template output just prior to writing the first document

  "eatezipkinindextemplate_gettraces_returnssuccess-dependency_template": {
    "order": 0,
    "index_patterns": [
      "eatezipkinindextemplate_gettraces_returnssuccess-dependency-*"
    ],
    "settings": {
      "index": {
        "number_of_shards": "5",
        "number_of_replicas": "1",
        "requests": {
          "cache": {
            "enable": "true"
          }
        }
      }
    },
    "mappings": {
      "enabled": false
    },
    "aliases": {}
  },
  "eatezipkinindextemplate_gettraces_returnssuccess-span_template": {
    "order": 0,
    "index_patterns": [
      "eatezipkinindextemplate_gettraces_returnssuccess-span-*"
    ],
    "settings": {
      "index": {
        "number_of_shards": "5",
        "number_of_replicas": "1",
        "requests": {
          "cache": {
            "enable": "true"
          }
        }
      }
    },
    "mappings": {
      "_source": {
        "excludes": [
          "_q"
        ]
      },
      "dynamic_templates": [
        {
          "strings": {
            "mapping": {
              "norms": false,
              "ignore_above": 256,
              "type": "keyword"
            },
            "match_mapping_type": "string",
            "match": "*"
          }
        }
      ],
      "properties": {
        "traceId": {
          "norms": false,
          "type": "keyword"
        },
        "duration": {
          "type": "long"
        },
        "remoteEndpoint": {
          "dynamic": false,
          "type": "object",
          "properties": {
            "serviceName": {
              "norms": false,
              "type": "keyword"
            }
          }
        },
        "localEndpoint": {
          "dynamic": false,
          "type": "object",
          "properties": {
            "serviceName": {
              "norms": false,
              "type": "keyword"
            }
          }
        },
        "_q": {
          "norms": false,
          "type": "keyword"
        },
        "timestamp_millis": {
          "format": "epoch_millis",
          "type": "date"
        },
        "name": {
          "norms": false,
          "type": "keyword"
        },
        "annotations": {
          "enabled": false
        },
        "tags": {
          "enabled": false
        }
      }
    },
    "aliases": {}
  },
  "eatezipkinindextemplate_gettraces_returnssuccess-autocomplete_template": {
    "order": 0,
    "index_patterns": [
      "eatezipkinindextemplate_gettraces_returnssuccess-autocomplete-*"
    ],
    "settings": {
      "index": {
        "number_of_shards": "5",
        "number_of_replicas": "1",
        "requests": {
          "cache": {
            "enable": "true"
          }
        }
      }
    },
    "mappings": {
      "enabled": true,
      "properties": {
        "tagValue": {
          "norms": false,
          "type": "keyword"
        },
        "tagKey": {
          "norms": false,
          "type": "keyword"
        }
      }
    },
    "aliases": {}
  }
}

[codefromthecrypt]

spent some time this 🎄 on this. eyes crossed then I noticed the wrong template was used. Eventually, figured out that 7.10 was mistaken for 7.1