plg_system_webauthn RTL css

[brianteeman]

I dont believe this class is used in core but it is clearly wrong for an rtl site. So this PR changes it to a logical property so that it works the same in RTL and LTR.

Code review

[Quy]

I have tested this item :white_check_mark: successfully on 6503d4095bf51280360a706f14c4236feec1594b

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[viocassel]

I have tested this item :white_check_mark: successfully on 6503d4095bf51280360a706f14c4236feec1594b

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[alikon]

RTC

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[wilsonge]

Thanks!

[brianteeman]

thanks