(core): change compose

todo-workspace/backend/compose.yaml

@@ -2,8 +2,8 @@ services:
   postgres:
     image: 'postgres:latest'
     environment:
-      - 'POSTGRES_DB=mydatabase'
-      - 'POSTGRES_PASSWORD=secret'
-      - 'POSTGRES_USER=myuser'
+      - 'POSTGRES_DB=${POSTGRES_DB}'
+      - 'POSTGRES_PASSWORD=${POSTGRES_PASSWORD}'
+      - 'POSTGRES_USER=${POSTGRES_USER}'
     ports:
       - '5432'