MOBILE-3833 qr: Set color-scheme to normal when open QR scanner
MOBILE-3833 qr: Set color-scheme to normal when open QR scanner

For some reason leaving this value to 'light dark' displays a black screen in Android

reskit/moodlemobile,reskit/moodlemobile,reskit/moodlemobile,reskit/moodlemobile,reskit/moodlemobile,reskit/moodlemobile