Improve preload links

[everdimension]

Currently we have this warning being reported by Chrome:

The resource <URL> was preloaded using link preload but not used within a few seconds from the window's load event.

This is because we statically put some images into https://github.com/zeriontech/zerion-wallet-extension/blob/506858467162f7aa683816d9a3ec707392e1f2eb/src/ui/popup.html#L34-L51

I think this should be fixed by programmatically creating these elements by the components that need them