When calling a collection post operation and if forgot to include a body then the api should handle this gracefully and return a 400 error instead of 500.

Currently it tries to validate "null" because controller result is null and symfony validator obviously doesn't like it.

Response from api:

{  
   "@context":"\/contexts\/Error",
   "@type":"hydra:Error",
   "hydra:title":"An error occurred",
   "hydra:description":"Cannot validate values of type \u0022NULL\u0022 automatically. Please provide a constraint."
}