[web] Log the QR code to the console

Summary:
Using this URL as a deep link should allow logging in using a simulator as a primary device.

https://linear.app/comm/issue/ENG-10168/improve-qr-login-flow-on-dev

Test Plan: Check in the console if the link is displayed.

Reviewers: kamil, bartek

Reviewed By: kamil

Subscribers: ashoat

Differential Revision: https://phab.comm.dev/D14314