iFrame redirect issue with Shopify oAuth
I have setup grant with my Shopify embedded app using Nextjs API routes. So far the app installs fine and goes through the oAuth process as expected. 

However, if I change my scopes from the ones originally installed what I would expect is to be taken back to the oAuth process to update the scopes. However, it seems as though the redirect from grant seems to be blocked by iframe security (shopify embedded apps are loaded in iframes)

**The general problem is this:**
1. Install app normally
2. Change the scopes
3. In shopify dashboard, click on app to load it
4. Shopify opens the app in an iframe and calls the app url to load it
5. Grant detects that the scope has changed and attempts to redirect to the oauth screen
6. (on Firefox 103.0.2) The embedded app iframe shows `To protect your security, <shopify store url> will not allow Firefox to display the page if another site has embedded it. To see this page, you need to open it in a new window.` 

You can then click on 'Open site in new window' and it opens the oAuth screen as expected, however, this is not ideal for customers for obvious reasons.

The url it is trying to show/redirect to is `https://<shopifystore>.myshopify.com/admin/oauth/request_grant?access_change_uuid=<uuid>&client_id=<clientid>`

I was able to set this up to work in the past just by using NextJS `request.redirect(<oauthurl>)` - so I know its possible.

My guess is that somewhere in grant it is trying to send the URL instead of redirect - is there a setting that can change this? Its totally possible this might be an issue on Shopify's side, although I don't think so.