Fix size of collapsible section buttons in navigation sidebar

What does this MR do and why?

At some point the height of a collapsible section became 29px instead of 32px

Screenshots or screen recordings

Before	After

How to set up and validate locally

1. Use the new navigation to navigate to Your work , a Group , and Project
2. Compare the differences of nav items with a chevron to other pages. They should all be 32px in height

MR acceptance checklist

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• I have evaluated the MR acceptance checklist for this MR.