[Glitch] Change how CDN_HOST is passed down to make assets build reproducible

Port 4c45b43cb8 to glitch-soc

Signed-off-by: Thibaut Girka <thib@sitedethib.com>

app/javascript/core/common.js

@@ -1,5 +1,6 @@
 //  This file will be loaded on all pages, regardless of theme.
 
+import 'packs/public-path';
 import 'font-awesome/css/font-awesome.css';
 
 require.context('../images/', true);