feat: delete icons sprite, use gravity icons

[artemmufazalov]

1. In many places we used icons from sprite. It's not very handy
2. Since we used our own icons, they may differ from the icons in components from uikit, thus we may have several versions of the same icon on one page

Deleted sprite, replaced most of the icons with uikit versions

Test stand: https://nda.ya.ru/t/lQGqdSKK768yCA

[artemmufazalov]

Added svgs that was in AppIcons

[Raubzeug]

Let's also use this library for illustrations? https://github.com/gravity-ui/illustrations

[artemmufazalov]

Let's also use this library for illustrations? https://github.com/gravity-ui/illustrations

I checked it and I'm not ready to use it yet. It has hardcoded colors in some places, without proper themisation this images don't fit (they're orange, our theme is blue)

I created issue for this: gravity-ui/illustrations#4