title: Azure Search CreateIndexAsync fails with CamelCase field names FieldBuilder
body: <p>Azure Search V11 <br>
  I can't get this to work. But with the standard FieldBuilder the index is created.</p>
  <pre><code>private static async Task CreateIndexAsync(SearchIndexClient indexClient, string indexName, Type type)
  {
      var builder = new FieldBuilder
      {
          Serializer = new JsonObjectSerializer(new JsonSerializerOptions {PropertyNamingPolicy = new CamelCaseNamingPolicy()})
      };
      var searchFields = builder.Build(type).ToArray();
      var definition = new SearchIndex(indexName, searchFields);
  
      await indexClient.CreateIndexAsync(definition);
  }
  </code></pre>
  <p>`<br></p>
  <pre><code>public class CamelCaseNamingPolicy : JsonNamingPolicy
  {
       public override string ConvertName(string name)
       {
           return char.ToLower(name[0]) + name.Substring(1);
       }
  }
  </code></pre>