fix prod icons

Summary:
Previously we had requested non existing icons. This fixes missing icons on pixel dense screens (macbook pro, 4k screens).

I could add x4, x5 icons as well. Though they are no better than x3. Even x3 is pretty raterized. Ideally we should be serving icons with higher resolution and scaling them down instead of doing this. Even better use SVG icons which we do not have.

Reviewed By: LukeDefeo

Differential Revision: D50454271

fbshipit-source-id: cda90972abb56069e160ddefdc6de460c49d06c0

desktop/flipper-ui-core/src/utils/icons.tsx

@@ -11,7 +11,7 @@ import {getRenderHostInstance} from 'flipper-frontend-core';
 import {IconSize} from '../ui/components/Glyph';
 
 const AVAILABLE_SIZES: IconSize[] = [8, 10, 12, 16, 18, 20, 24, 28, 32];
-const DENSITIES = [1, 1.5, 2, 3, 4];
+const DENSITIES = [1, 2, 3];
 
 export type Icon = {
   name: string;