Add `gap` property to StyleSheet API

[JuanM04]

Is your feature request related to a problem? Please describe. When generating dynamic content (like tables), gap provides a simple way of creating spaces between elements inside a flexbox without necessity of doing weird things with margins and widths.

Describe the solution you'd like Maybe something like gap, gapVertical and gapHorizontal.

[jeetiss]

@react-pdf uses yoga layout under hood and gap should be implemented in yoga first

Upvote this issue if you agree. https://github.com/facebook/yoga/issues/812

[process0]

There seems to finally be activity on the PR that implements gap for yoga https://github.com/facebook/yoga/pull/1116

[axel7083]

Since the PR is still pending, here is a solution I found which work fine: flex-gap-in-unsupported-browsers

[ajayvikas]

Seems it has been implemented in yoga.