[csharp-netcore] Avoid reserved words in CodegenProperty name

[devhl-labs]

This will locate any CodegenProperty#name and prefix with "Property" if the name, or the CamelCaseLambda version of the name, is a reserved word. If we don't do this, then the CamelCaseLambda version will prefix an underscore. The underscore can break the mapping between the json property and the class property.

fixes #11868 (comment)

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@mandrean (2017/08) @frankyjuang (2019/09) @shibayan (2020/02) @Blackclaws (2021/03) @lucamazzanti (2021/05)

[devhl-labs]

I switched from using a suffix to a prefix. It was initially a prefix because of worry I had which shouldn't be an issue in hindsight.

[devhl-labs]

This PR fixes this scenario. Without the fix we get this. The underscore on the internal property causes the deserialization to fail.

public TestModel(bool? active = default, Guid? modelUuid = default, bool? _internal = default)
{
    Active = active;
    ModelUuid = modelUuid;
    Internal = _internal;
}

With this fix, we get this:

  public TestModel(bool? active = default, Guid? modelUuid = default, bool? internalProperty = default)
  {
      Active = active;
      ModelUuid = modelUuid;
      InternalProperty = internalProperty;
  }

Here is the same thing when using RestSharp:

public TestModel(bool active = default(bool), Guid modelUuid = default(Guid), bool _internal = default(bool))
{
    this.Active = active;
    this.ModelUuid = modelUuid;
    this.Internal = _internal;
}

public TestModel(bool active = default(bool), Guid modelUuid = default(Guid), bool internalProperty = default(bool))
{
    this.Active = active;
    this.ModelUuid = modelUuid;
    this.InternalProperty = internalProperty;
}

Here is the yaml used to test this.

openapi: 3.0.3
info:
  title: Test openapi spec file for parameterless constructor issue
  version: v1
paths:
  '/hello':
    get:
      responses:
        '200':
          description: Success
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/TestModel'

components:
  schemas:
    TestModel:
      description: Model information
      properties:
        active:
          description: active description
          type: boolean
        model_uuid:
          description: model uuid description
          type: string
          format: uuid
        internal:
          description: internal value
          type: boolean

[devhl-labs]

Closing in favor of better implementation at #13681