Non-compliant JSONAPI tests

[beauby]

While investigating the relevance of virtual values for relationships with the json_api adapter, I came across those tests, which expect an output that is not JSONAPI compliant:

• test_has_many_with_no_serializer
  • expected output: {:data=>{:id=>"1", :type=>"posts", :relationships=>{:tags=>{:data=>[{"attributes"=>{"id"=>1, "name"=>"#hash_tag"}}]}}}}
• test_has_many_with_virtual_value
  • expected output: {:data=>{:id=>"1", :type=>"virtual_values", :relationships=>{:maker=>{:data=>{:id=>1}}, :reviews=>{:data=>[{:id=>1}, {:id=>2}]}}}}
• test_has_one_with_virtual_value
  • expected output: {:data=>{:id=>"1", :type=>"virtual_values", :relationships=>{:maker=>{:data=>{:id=>1}}, :reviews=>{:data=>[{:id=>1}, {:id=>2}]}}}}

[joaomdmoura]

I know this sound tricky, and we really love and want to help ppl to use json-api, but I'd keep virtual value for now, mostly because is something some ppl are kind used to, and it does not impact others that want to follow the convention.
The no_serializer could be overridden to follow the conventions though