title: Access to XMLHttpRequest at Access to XMLHttpRequest has been blocked by CORS policy
body: <p>My application has angular front end and springboot back end.
  When i call backend api (localhost:8080/test) from frontend (localhost:4200) it gives an Error.</p>
  
  <pre><code>Access to XMLHttpRequest at http://localhost:8080/api/XXX/1 from origin http://localhost:4200 has been blocked by CORS policy: 
  Response to preflight request doesn't pass access control check: 
  The value of the 'Access-Control-Allow-Credentials' header in the response is '' which must be 'true' when the request's credentials mode is 'include'. 
  The credentials mode of requests initiated by the XMLHttpRequest is controlled by the withCredentials attribute.
  </code></pre>
  
  <p>My request hearder information as below,</p>
  
  <pre><code>Request URL: http://localhost:8080/api/testSuite/execute/1
  Referrer Policy: no-referrer-when-downgrade
  Provisional headers are shown
  Accept: application/json
  Content-Type: application/json
  Referer: http://localhost:4200/testSuite
  Sec-Fetch-Mode: cors
  User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/76.0.3809.100 Safari/537.36
  </code></pre>