Refresh Heroku related thingy for heroku-24 stack (mastodon#31135)

Author: zunda

.profile

@@ -1,5 +1,5 @@
-ffmpeg
-libopenblas0-pthread
-libpq-dev
-libxdamage1
-libxfixes3
+libidn12
+# for idn-ruby on heroku-24 stack
+
+# use https://github.com/heroku/heroku-buildpack-activestorage-preview
+# in place for ffmpeg and its dependent packages to reduce slag size

Aptfile

@@ -11,4 +11,4 @@ worker: bundle exec sidekiq
 #
 # and let the main app use the separate app:
 #
-# heroku config:set STREAMING_API_BASE_URL=wss://<streaming-app>.herokuapp.com -a <main-app>
+# heroku config:set STREAMING_API_BASE_URL=wss://<streaming-app-random>.herokuapp.com -a <main-app>

Procfile

@@ -90,15 +90,22 @@
     }
   },
   "buildpacks": [
+    {
+      "url": "https://github.com/heroku/heroku-buildpack-activestorage-preview"
+    },
     {
       "url": "https://github.com/heroku/heroku-buildpack-apt"
     },
+    {
+      "url": "heroku/nodejs"
+    },
     {
       "url": "heroku/ruby"
     }
   ],
   "scripts": {
     "postdeploy": "bundle exec rails db:migrate && bundle exec rails db:seed"
   },
-  "addons": ["heroku-postgresql", "heroku-redis"]
+  "addons": ["heroku-postgresql", "heroku-redis"],
+  "stack": "heroku-24"
 }