unicode: remove variation selectors from IsGraphic and IsPrint

[saranshsaini]

IsGraphic and IsPrint return true for Variation Selectors, which are invisible.

This just adds a check to not include those, and a test to verify.

Fixes #73673

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Patch Set 1:

(1 comment)

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Message from Saransh Saini:

Patch Set 2:

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Patch Set 2:

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Message from Saransh Saini:

Patch Set 2:

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