title: .net core 3 not having ReferenceLoopHandling in AddJsonOptions
body: <p>My csproject file is indicating: <code>&lt;TargetFramework&gt;netcoreapp3.0&lt;/TargetFramework&gt;</code></p>
  
  <p>In my startup im using the followinhg:</p>
  
  <pre><code> services.AddMvc(x =&gt; x.Filters.AddService&lt;TransactionFilter&gt;())
          .AddJsonOptions(options =&gt; options.JsonSerializerOptions... )
  </code></pre>
  
  <p>But, ReferenceLoopHandling  is not available inside <code>options.JsonSerializerOptions</code>.</p>
  
  <p><a href="https://i.stack.imgur.com/0cqfc.png" rel="noreferrer"><img src="https://i.stack.imgur.com/0cqfc.png" alt="enter image description here"></a></p>
  
  <pre><code>&lt;Project Sdk="Microsoft.NET.Sdk.Web"&gt;
  
    &lt;PropertyGroup&gt;
      &lt;TargetFramework&gt;netcoreapp3.0&lt;/TargetFramework&gt;
    &lt;/PropertyGroup&gt;
  
    &lt;ItemGroup&gt;
      &lt;PackageReference Include="FluentNHibernate" Version="2.1.2" /&gt;
      &lt;PackageReference Include="FullContact.Contacts.API" Version="1.0.3" /&gt;
      &lt;PackageReference Include="Google.Cloud.Storage.V1" Version="2.3.0" /&gt;
      &lt;PackageReference Include="Microsoft.AspNetCore.Authentication.JwtBearer" Version="2.2.0" /&gt;
      &lt;PackageReference Include="Microsoft.AspNetCore.Mvc.Cors" Version="2.2.0" /&gt;
      &lt;PackageReference Include="Microsoft.AspNetCore.Mvc.Formatters.Json" Version="2.2.0" /&gt;
      &lt;PackageReference Include="Microsoft.IdentityModel.Tokens" Version="5.5.0" /&gt;
      &lt;PackageReference Include="MySql.Data" Version="8.0.17" /&gt;
      &lt;PackageReference Include="piplclient" Version="5.0.9" /&gt;
      &lt;PackageReference Include="System.IdentityModel.Tokens.Jwt" Version="5.5.0" /&gt;
    &lt;/ItemGroup&gt;
  
  &lt;/Project&gt;
  </code></pre>