Fix(web-react): Do not render empty style prop

[literat]

Description

When not using UNSAFE_style prop, the default {} is rendered into the DOM. Using undefined instead.

Additional context

Every snapshot in product, like KukAD:

<ul
        className="Tabs"
        role="tablist"
        style={{}} // <- here
>

Issue reference

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[github-actions]

coverage: 70.462% (-9.2%) from 79.617%
when pulling 4121e2f on fix/web-react-do-not-render-empty-style
into 02c3ddf on main.

[github-actions]

coverage: 70.462% (-9.2%) from 79.617%
when pulling 4121e2f on fix/web-react-do-not-render-empty-style
into 02c3ddf on main.