ASSET_HOST is wrong env variable. Fix to CDN_HOST (#6372)

config/webpack/configuration.js

@@ -27,7 +27,7 @@ function formatPublicPath(host = '', path = '') {
 
 const output = {
   path: resolve('public', settings.public_output_path),
-  publicPath: formatPublicPath(env.ASSET_HOST, settings.public_output_path),
+  publicPath: formatPublicPath(env.CDN_HOST, settings.public_output_path),
 };
 
 module.exports = {

lib/mastodon/premailer_webpack_strategy.rb

@@ -2,7 +2,7 @@
 
 module PremailerWebpackStrategy
   def load(url)
-    asset_host = ENV['ASSET_HOST'] || ENV['WEB_DOMAIN'] || ENV['LOCAL_DOMAIN']
+    asset_host = ENV['CDN_HOST'] || ENV['WEB_DOMAIN'] || ENV['LOCAL_DOMAIN']
 
     if Webpacker.dev_server.running?
       asset_host = "#{Webpacker.dev_server.protocol}://#{Webpacker.dev_server.host_with_port}"