[Feat]: --mod-* tokens for sp-tabs-overflow shadow color

[Rocss]

Code of conduct

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Impacted component(s)

sp-tabs-overflow

Description of the requested feature

sp-tabs-overflow doesn't have mod token to override the -sp-tabs-overflow-shadow-color , sp-tabs-overflow-next-button-left and sp-tabs-overflow-next-button-right for left and right button. Can it be added in the future? The reason is that I'm adding overflow tabs to the Properties Inspector, which has a background color of spectrum-gray-50, while the button shadow uses -spectrum-gray-100

Mockups or screenshots

Implementation notes or ideas

No response