How to use wildcard field in Aiven's ElasticSearch?

I wanted to test the new wildcard field type in my ElasticSearch instance (Aiven).

I've tried this:

PUT /wildcard_test
{
  "mappings" : {
      "properties" : {
        "wildcard_field" : {
          "type" : "wildcard"
          }
        }
  }
}

And I'm getting this response:

{
  "error" : {
    "root_cause" : [
      {
        "type" : "mapper_parsing_exception",
        "reason" : "No handler for type [wildcard] declared on field [wildcard_field]"
      }
    ],
    "type" : "mapper_parsing_exception",
    "reason" : "Failed to parse mapping [_doc]: No handler for type [wildcard] declared on field [wildcard_field]",
    "caused_by" : {
      "type" : "mapper_parsing_exception",
      "reason" : "No handler for type [wildcard] declared on field [wildcard_field]"
    }
  },
  "status" : 400
}

Here are the info regarding the instance:

GET /

{
  "name" : "...",
  "cluster_name" : "...",
  "cluster_uuid" : "...",
  "version" : {
    "number" : "7.9.3",
    "build_flavor" : "unknown",
    "build_type" : "unknown",
    "build_hash" : "c4138e51121ef06a6404866cddc601906fe5c868",
    "build_date" : "2020-10-16T10:36:16.141335Z",
    "build_snapshot" : false,
    "lucene_version" : "8.6.2",
    "minimum_wire_compatibility_version" : "6.8.0",
    "minimum_index_compatibility_version" : "6.0.0-beta1"
  },
  "tagline" : "You Know, for Search"
}

GET /_license

{
  "error" : {
    "root_cause" : [
      {
        "type" : "invalid_index_name_exception",
        "reason" : "Invalid index name [_license], must not start with '_'.",
        "index_uuid" : "_na_",
        "index" : "_license"
      }
    ],
    "type" : "invalid_index_name_exception",
    "reason" : "Invalid index name [_license], must not start with '_'.",
    "index_uuid" : "_na_",
    "index" : "_license"
  },
  "status" : 400
}

My understanding is that this feature is provided by X-Pack, which I don't whether or not is included in Aiven's service. Is there some way to make this work?

Although the wildcard field type was indeed added in v7.9, it's (unfortunately) only available as part of an X-Pack subscription and I presume the one running on Aiven is OSS which is missing this and other X-Pack features.