When we handle pixel ratios in .png files, we were rounding the pixel
ratio to the nearest integer. This mean that if an image had a pixel
ration less than 0.5, it would get rounded to zero. This would cause a
divide-by-zero on the width & height of the image which would crash the
app.
This has a couple fixes:
- we ignore pixel ratios less that 1
- we perform rounding _after_ we apply the pixel ratio to the
width/height
### Change Type
- [x] `patch` — Bug fix
### Test Plan
1. Upload this funky image:
2. Check the app doesn't crash
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