Use JsonIgnoreProperties to fix Infinite recursion (StackOverflowError)

[wing328]

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Description of the PR

To fix #241

[jmini]

Tested with:

openapi: "3.0.0"
info:
  description: "test"
  version: "1.0.0"
  title: "myTest"

  contact:
    email: "[email protected]"

servers:
- url: "http://localhost:9998/v1"

tags:
- name: "users"

paths:
  /users/create/{username}:
    post:
      tags:
      - "user"
      operationId: "createUser"
      parameters:
      - name: "username"
        in: "path"
        required: true
        schema:
          type: "string"
      responses:
        200:
          description: "The User just created"
          content:
            application/json:
              schema:
                $ref: "#/components/schemas/User"
components:
  schemas: 
    User:
      allOf:
        - $ref: "#/components/schemas/UserDetail"
        - type: "object"
          description: "The User"
          properties:
            id:
              type: integer
    UserDetail:
      type: "object"
      description: "Detail of a User"
      properties:
        name:
          type: "string"
          description: "the name of the user"

and this code:

@Test
public void testBuildSupportFileBundle() throws Exception {
    File output = Files.createTempDirectory("test").toFile();

    final CodegenConfigurator configurator = new CodegenConfigurator()
            .setGeneratorName("java")
            .setLibrary(JavaClientCodegen.OKHTTP_GSON)
            .setInputSpec(/* path to yaml */)
            .setOutputDir(output.getAbsolutePath().replace("\\", "/"));

    final ClientOptInput clientOptInput = configurator.toClientOptInput();
    MockDefaultGenerator generator = new MockDefaultGenerator();

    try {
        System.setProperty("debugSupportingFiles", "true");
        generator.opts(clientOptInput).generate();
    } finally {
        System.clearProperty("debugSupportingFiles");
    }
}

I wanted to add it as unit test, but the issue is only in the logs, it makes it difficult to write a unit-test for this.

[wing328]

@jmini I've filed #904 add a test case catching the issue moving forward.