fix: reduces number of sidekiq threads

docker-compose.yml

@@ -68,7 +68,7 @@ services:
     restart: always
     image: ghcr.io/mastodon/mastodon:v4.1.18
     env_file: .env.production
-    command: bundle exec sidekiq
+    command: bundle exec sidekiq -c 2
     depends_on:
     - db
     - redis