Android: list of enums generates syntax error due to mustache HTML encoding

Bug Report Checklist

• Have you provided a full/minimal spec to reproduce the issue?
• Have you validated the input using an OpenAPI validator (example)?
• What's the version of OpenAPI Generator used?
• Have you search for related issues/PRs?
• What's the actual output vs expected output?
• [Optional] Bounty to sponsor the fix (example)

Description

In my Swagger 2 spec, I have a Definition with an array property. Its items are defined as strings with an enum-erated list of values. When I use the "android" generator, it incorrectly HTML-encodes the List definition, resulting in a syntax error.

The property looks like:

        "gender": {
          "type": "array",
          "items": {
            "type": "string",
            "enum": [
              "Male",
              "Female"
            ]
          }
        },

and the resulting Java code looks like:

  public enum List<GenderEnum> {
     Male,  Female, 
  };

openapi-generator version

4.0.0-SNAPSHOT

OpenAPI declaration file content or url

https://gist.github.com/jacobweber/c21e944d6e627a92ddcfd02242aca117

Command line used for generation

java -jar /path/to/openapi-generator-cli.jar generate -i /path/to/spec.json -g android -o /path/to/output
cd /path/to/output
mvn clean package

Steps to reproduce

See above

Related issues/PRs

None

Suggest a fix

None

Start with the provided Swagger 2 definition and run the documented android generator command to reproduce the generated enum. Inspect the generated Java model containing the array enum and verify that the output no longer HTML-encodes the List type and compiles with Maven.