[BUG][CSharp] Bug generating code with Enum having maxLength property

Created by: shwetashukla

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?
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Description

We have an open api spec version 2.0 and we are trying to generate code in csharp . We have an issue in generated SDKif the property whose type is string is an enum and has maxLength specified . Please refer line 121 in attached contract . petstore.txt

Below is the code in csharp and the one in bold throws error.

// Status (string) maxLength if(this.Status != null && this.Status.Length > 20) { yield return new System.ComponentModel.DataAnnotations.ValidationResult("Invalid value for Status , length must be less than 20.", new [] { "Status " }); }

openapi-generator version

3.3.4

OpenAPI declaration file content or url

petstore.txt

Command line used for generation

Steps to reproduce

Related issues/PRs

Suggest a fix

csharp code should be like The code should be like this.Status.ToString().Length.

In the snapshot below we can make fix