fix(preset-mini): remove num === 0 in px handler to fix offset utility issues

[henrikvilhelmberglund]

This PR removes a num === 0 check in the px handler which returned 0 which broke a bunch of offset-utilities (ring-offset-0, underline-offset-0). This means it returns 0px now and these utilities work again.

The num === 0 check is still there for the rem handler so inset-0 still gives a 0 result. (I'm not sure why this is better than 0px though)

It's possible there's a better way to fix this, in that case feel free to close this PR.

fixes #3196

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[zyyv]

The num === 0 check is still there for the rem handler so inset-0 still gives a 0 result. (I'm not sure why this is better than 0px though)

Cause #2153 changes to produce this issue that i'm not consided it. And thanks for your feedback, I'll consider if there's a better way to fix it or revert it.

[henrikvilhelmberglund]

A fun(?) thing I noticed is that decoration-offset-0 in UnoCSS seems broken in Chrome/Brave, I get something like this. Very strange...

edit: this seems caused by a missing text-underline-position: from-font; see https://bugs.chromium.org/p/chromium/issues/detail?id=1172623

[henrikvilhelmberglund]

The num === 0 check is still there for the rem handler so inset-0 still gives a 0 result. (I'm not sure why this is better than 0px though)

Cause #2153 changes to produce this issue that i'm not consided it. And thanks for your feedback, I'll consider if there's a better way to fix it or revert it.

Do you want to merge it like this or did you have some other solution in mind?