Set an explicit username/password for Postgres in the swarm and k8s files too

result/docker-compose.test.yml

@@ -47,6 +47,9 @@ services:
 
   db:
     image: postgres:9.4
+    environment:
+      POSTGRES_USER: "postgres"
+      POSTGRES_PASSWORD: "postgres"
     volumes:
       - "db-data:/var/lib/postgresql/data"
     networks: