title: assert Json Validation Errors does not work
body: <p>I am not an expert and I could not find anything about my error. I hope someone can help me to understand my error.</p>
  
  <p>I am trying to test the validation of the required attributes of a POST request in Laravel.</p>
  
  <p><strong>TEST</strong></p>
  
  <p>I am using the <code>assertJsonValidationErrors</code> method to validate the JSON errors from my controller.</p>
  
  <pre><code>/** @test */
  public function name_email_password_required_in_creation()
  {
      $response = $this-&gt;post('/users', [
          'contact' =&gt; '545678987'
      ]);
      $response-&gt;assertJsonValidationErrors(['name','password','email']);
  }
  </code></pre>
  
  <p><strong>Controller</strong></p>
  
  <pre><code>$validator = Validator::make($request-&gt;all(),[
          'name' =&gt; 'required',
          'email' =&gt; 'required|unique:users,email',
          'password' =&gt; 'required',
      ]);
  
      if ($validator-&gt;fails()) {
          return response()-&gt;json($validator-&gt;errors(), 400);
      }
  </code></pre>
  
  <p>Error:</p>
  
  <p><strong>1) Tests\Feature\UsersTest::name_email_password_required_in_creation</strong>
  <strong>Failed to find a validation error in the response for key: 'name'</strong></p>
  
  <p><strong>Response does not have JSON validation errors.
  Failed asserting that an array has the key 'name'.</strong></p>
  
  <p>I applied inside the test a </p>
  
  <p><code>dd($response-&gt;getContent());</code> to see what is happening and in the response is:</p>
  
  <p><code>"{"name":["The name field is required."],"email":["The email field is required."],"password":["The password field is required."]}"</code></p>
  
  <p>It seems to be a <strong>string</strong> but I don't know if it is causing the error, because the JSON contains the key fields errors.</p>
  
  <p>I do know how to solve it. Thanks in advance.</p>