title: Microsoft Graph - whether tenant exists
body: <p>My workflow has logic to create "tenant" on Microsoft (like: <code>mycompany.onmicrosoft.com</code>). I want to be sure, that this <code>mycompany.onmicrosoft.com</code> is not registered before. Any way to validate it via Microsoft Graph or any other API?</p>
  
  <p>Thank you!</p>