[4.0] Fancy selectbox fix

[brianteeman]

This is a replacement to the merged PR #30739 for atum and to identical code in cassiopeia

It does exactly the same thing but by using css logical properties we avoid the need to maintain both an LTR and an RTL version

There is no visual change.

[Quy]

I have tested this item ✅ successfully on b282797

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[Shubhamverma2796]

I have tested this item ✅ successfully on b282797

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[richard67]

RTC

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[khu5h1]

I have tested this item ✅ successfully on b282797

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[richard67]

Setting RLDQ label so release leads can decide about usage of inset-inline regarding our browser support policy.

[pritam825]

I have tested this item ✅ successfully on b282797

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[wilsonge]

Thanks!

[brianteeman]

Thanks