title: AWS API-Gateway Cognito Authorizer not working with a valid Token
body: <p>A simple API endpoint, with a <strong>Cognito User Pool Authorizer</strong>, when using the <strong>Authorizer Test</strong> button ( or using postman/Insomnia ) with a valid token fails ( Screenshot bellow ):</p>
  
  <p><a href="https://i.stack.imgur.com/i1vSd.png" rel="noreferrer"><img src="https://i.stack.imgur.com/i1vSd.png" alt="enter image description here"></a></p>
  
  <p>I know the token is valid as I can make a successful call to the Cognito user pool <code>user-info</code> end-point using the same token and get the desired response back.
  Also removing the authorizer ( setting it to <code>None</code> ), will return the desired response as well.
  I've tried both with and without <code>Bearer ...</code>, I've also tried to change the <code>Authorization</code> Token source to <code>method.request.header.Authorization</code> as I've found in <a href="https://stackoverflow.com/questions/46345005/aws-api-gateway-authorizer-cognito-user-pool-not-working-message-unauthor">some older Question</a> but immediately after saving, it changes it back to <code>Authorization</code>, while <code>method.response.header.Authorization</code> doesn't seem to work either.
  The API was deployed through a CloudFormation stack.</p>