chore: update demo qr (#4241)

## About the changes
<!-- Describe the changes introduced. What are they and why are they
being introduced? Feel free to also add screenshots or steps to view the
changes if they're visual. -->

Updates to use the new Demo QR


![image](https://github.com/Unleash/unleash/assets/707867/75065a45-5462-4230-b246-53fb52ea4fb5)