title: Why angular4 calls two times oauth/token?
body: <p>I have problem but didn't see what make that problem. I made one laravel+passport project and try with other angular4 project to "talk" with laravel project. This is <a href="https://github.com/sandeeprajoria/laravel-passport-angular" rel="nofollow noreferrer">start angular4 project</a>. But am stack. AS you can see in picture below <a href="https://i.stack.imgur.com/Cy6Qx.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/Cy6Qx.png" alt="multiple oauth_token calls"></a> when I click login it calls two times oauth/token to laravel project. Firstable time he have <code>Request method: Options</code>, and second one is OK and have <code>Request method: POST</code>. First one didn't return nothing and the other one return valid results with token and reset token. I don't see where is that first one triggered but second one is triggered after finished first request. Code where is placed click on login button is <a href="https://github.com/sandeeprajoria/laravel-passport-angular/blob/master/src/components/login/login.ts" rel="nofollow noreferrer">here</a>. </p>
  
  <p>Hope that someone can tell me what is the problem.</p>