v2: Top-level `tags` property incorrectly serialized in document writing

[captainsafia]

In 2.0.0-preview2, it appears that the tags property in the OpenAPI document isn't serialized correctly as a list of objects. For example, the following code:

using System;
using Microsoft.OpenApi.Models;
using Microsoft.OpenApi.Writers;
using System.IO;
using System.Globalization;

var document = new OpenApiDocument();

document.Tags = [new OpenApiTag { Name = "test" }];

var outputStringWriter = new StringWriter(CultureInfo.InvariantCulture);
var writer = new OpenApiJsonWriter(outputStringWriter);
document.SerializeAsV2(writer);
Console.WriteLine(outputStringWriter.ToString());

Produces the following document:

{
  "swagger": "2.0",
  "info": { },
  "paths": { },
  "tags": [
    "test"
  ]
}

Which in turn cannot be loaded by the serialization APIs without errors. This happens across all OpenAPI versions (SerializeAsV3, SerializeAsV31).

[MaggieKimani1]

This issue has now been fixed by this PR #1939