Avoid needlessly converting a QIcon to a pixmap

We can pass a QIcon directly here, which is better since it makes the widget responsible for picking the correct icon size
1 job for !6 with work/qicon in 4 minutes and 27 seconds (queued for 10 minutes and 3 seconds)
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Status Job ID Name Coverage
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passed #103201
linux kf5-qt5 qt5.15

00:04:27

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