Add 22px variants of the preferences icons

Since the sidebar view has been the default for some time now, we should have special pixel fitted versions made specifically for it too.

At a glance it might not seem that different but it helps with sharpness especially on the more detailed icons like preferences-smart-status, preferences-system-network-share-windows and preferences-virtualization-container.

Some icons on here could probably be improved but I'm not too sure how to do that without sacrificing some sharpness (preferences-desktop-cryptography, preferences-desktop-baloo)