Nested filtering on enum is broken

[maurei]

Description

Consider the models:

public class Article : Identifiable
{
    [Attr] public SomeEnum SomeEnum { get; set; }
}

public class Author : Identifiable
{
    [HasMany] public List<Article> Articles { get; set; }
}

then, the following does not work:

http://localhost:5000/v1/authors?include=articles&filter[articles.someEnum]=1

Error:

"title": "ArgumentException",
"detail": "'SomeEnum' is not a member of type 'System.Collections.Generic.List`1[Rs.Services.Clients.Models.Author]' (Parameter 'propertyOrFieldName')",
"status": "500"

Note that, however, the following does work:

http://localhost:5000/v1/articles?filter[someEnum]=1

[maurei]

This is actually a duplicate of #627