Testing | Sample view | Check response headers and problem code

[shivanshs9]

Write tests with a sample view to test all of the following behaviors:

• When response HTTP status is 200, content type is "application/json".
• When response HTTP status is 401, content type is "application/problem+json" and problem code is "not_authenticated".
• When response HTTP status is 404, content type is "application/problem+json" and problem code is "not_found".
• When response HTTP status is 500 (server error - crash your own view), content type is "application/problem+json" and problem code is "error".