Rendered QR code does not respect device pixel ratio

[uhthomas]

No description provided.

[uhthomas]

This is because QRious renders to a canvas. There are two options to resolve this:

1. Resize the canvas to match the new device pixel ratio on page size change.
2. Find a different library which outputs SVGs.

The second option is my preferred solution as it means there doesn't need to be any new code to watch for changes to the viewport which also means there's likely to be bugs.