[4.0] tab focus

[brianteeman]

When navigating with the keyboard a focus outline is applied to the tabs

However as can be seen in this enlargement the outline is cut on the right.

This PR adjusts the z-index to prevent that

There is a scss change so you will need to rebuild it for testing

[ChristineWk]

I have tested this item ✅ successfully on 598bca5

First try with Prebuilt Package was unsuccessful.
But after Clearing Browser Cache (FF) it was OK then.

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[RickR2H]

I have tested this item ✅ successfully on 598bca5

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[richard67]

RTC

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[wilsonge]

Thanks!

[brianteeman]

Thank you