title: AWS amplify add auth: how to add a redirect signin URI after executing the amplify cli
body: <p>Context: I was following a AWS tutorial to create iOS application using Amplify. One of the steps was to use 'amplify add auth' and specify the 'redirect signing URI'. For some reason the CLI didn't prompt me for the URL. 'amplify update auth' does not provide an option to specify the redirect URL.</p>
  <p>Question: How can I add redirect URL to the project, after executing the 'amplify add auth' command?</p>