Add extensions icons in Blender add-on/get extensions list

We do this cool / not so cool icons for extensions. They kind of main icon of extension:

But whey are visible only in Approval Queue:

And in the extension page:

Isn't that weird? Why to have icons and do not use them?

I think small icons won't spoil the attractiveness of ui, even if they are all very diverse, but will provide some additional recognition of familiar extensions (oh, I've seen this somewhere before)