Add CSS Support for text-box-trim

[Sentimers]

Add CSS support for text-box-trim.

text-box-trim is a CSS property that removes excess whitespace around text, which is useful for text-based layouts.

for more information about text-box-trim.
https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Properties/text-box-trim 

[Jon]

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