Improve icon generation to reduce cutoff

[TheAlexLichter]

Follow-up of #40
Thanks to 8c1f8e2, the generation is running through now but the icon is cut off when height > width.

It'd be ideal to termine whether height > width, then running sharp(input).resize(undefined, Math.floor(size)) and else running ``sharp(input).resize(Math.floor(size))`

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Result with current state:

Result with (harcoded) patch:

[kevinmarrec]

Yeah I didn't know what to do regarding not squared icons, if undefined on resize function works well I'm gonna do adjustments.

Thanks for feedback !

[kevinmarrec]

@manniL Could you provide the image you used please ? 💚

[TheAlexLichter]

Sure! https://gubutler.com/icon.png

[kevinmarrec]

@manniL Thanks, I found a better way to handle it, and also made splashs working with all icon sizes !

Closing through f342fa8

Released in v0.6.1 ✨

[TheAlexLichter]

Awesome!