feat(docker): replace all-in-one image with FrankenPHP and Caddy based image + discard other images

- use serversideup/php as a base image
- remove nginx unit base
- remove app / webserver images
- add bundle stage to remove pipeline dependency
- update docker setup docs
- edit gitlabci rules and release logic

modules/PremiumPodcasts/Models/SubscriptionModel.php

@@ -120,7 +120,7 @@ class SubscriptionModel extends Model
                 'status' => 'active',
             ])
             ->groupStart()
-            ->where('expires_at', null)
+            ->where('expires_at')
             ->orWhere('`expires_at` > UTC_TIMESTAMP()', null, false)
             ->groupEnd()
             ->first();