Post Body

1. Assert that a GET request to "/api/level16" returns a 400 status code.
2. Assert that a POST request to "/api/level16" returns a 200 status code.
3. Assert that a POST request to "/api/level16" with the following JSON:

   {
     "greeting": "Good morning"
   }

   returns:

   {
     "greeting": "Hiya~!" 
   }

🏃