Rename containers: backend -> bookmann, db -> bookmann_db

docker-compose.yml

@@ -3,6 +3,7 @@ version: "3.8"
 services:
   db:
     image: postgres:15-alpine
+    container_name: bookmann_db
     environment:
       POSTGRES_DB: ebookdb
       POSTGRES_USER: postgres
@@ -24,6 +25,7 @@ services:
     build:
       context: .
       dockerfile: ./backend/Dockerfile
+    container_name: bookmann
     environment:
       DATABASE_HOST: db
       DATABASE_PORT: 5432