Resolve "Sidebar text is getting cutoff in the new navigation"

What does this MR do and why?

Resolves #410158 (closed) by using default line-height. Small tweak to padding to compensate the now larger line-height.

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How to set up and validate locally

• I could only reproduce this issue in Firefox. Chrome seems to handle that better, but please verify the fix in both browsers. Also Safari if you have that 🍎
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MR acceptance checklist

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