QR code is missing required quiet zone, making it harder to read

[wklaebe]

The QR code that shows up in the bottom bar after clicking "submit" (or in the middle of the screen after clicking on it) does not have the required "quiet zone" of 4x module size and nominal reflectance value equal to that of the light modules described in the specification (see, for example, ISO/IEC 18004:2015 6.3.8). This makes it harder to scan.