AnyType serialization does not support Dictionary with empty string key

[stanislav-a-frolov]

Product

Hot Chocolate

Version

16.0.9

Link to minimal reproduction

https://github.com/stanislav-a-frolov/TestEmptyDictionaryKeys

Steps to reproduce

1. Setup executor with query field resolving to dictionary with empty string key, add type converter to JsonElement

        var executor = await new ServiceCollection()
            .AddGraphQL()
            .AddQueryType(q => q.Field("data").Resolve(ctx => new Dictionary<string, object?>() { { "", 1 } }).Type<AnyType>())
            .AddTypeConverter<Dictionary<string, object?>, JsonElement>(value => JsonSerializer.SerializeToElement(value))
            .BuildRequestExecutorAsync();

2. Execute query, get errors

        var response = await executor.ExecuteAsync("query { data }");
        var operationResult = response.ExpectOperationResult();
        Assert.Empty(operationResult!.Errors); // fail: Value cannot be null. (Parameter 'propertyName')

What is expected?

Result is expected to be serialized with empty string field without errors as it was in HC 15

What is actually happening?

ArgumentNullException is thrown at ResultElement.SetPropertyName due to empty span

Relevant log output

Additional context

No response