[Bug] Secondary tabs flickering on hover

[jvorheis]

The secondary tabs component has a flickering UI issue. The bottom border will flicker after the first selection is made. As seen in this gif. https://www.screencast.com/t/6oxbc1aA0

[staceyshk]

This is happening in chrome for me, consider it verified.

[jvorheis]

I was seeing this in Chrome Version 91.0.4472.101 (Official Build) (x86_64) while viewing it in Storybook.