Update docker-compose file

Author: tiagomota

scripts/docker-compose.yml

@@ -1,9 +1,12 @@
-postgres:
-  image: postgres:latest
-  container_name: postgres
-  environment:
-    - "TZ=Europe/Amsterdam"
-    - "POSTGRES_USER=docker"
-    - "POSTGRES_PASSWORD=docker"
-  ports:
-    - "5432:5432"  # credentials (docker:docker)
+version: "3"
+
+services:
+  postgres:
+    image: postgres:latest
+    container_name: postgres
+    environment:
+      - "TZ=Europe/Amsterdam"
+      - "POSTGRES_USER=docker"
+      - "POSTGRES_PASSWORD=docker"
+    ports:
+      - "5432:5432"  # credentials (docker:docker)