add pg_admin to compose

compose.yaml

@@ -37,3 +37,12 @@ services:
       timeout: 5s
       retries: 5
       start_period: 10s
+  pg_admin:
+    image: dpage/pgadmin4
+    environment:
+      PGADMIN_DEFAULT_EMAIL: example@example.com
+      PGADMIN_DEFAULT_PASSWORD: example
+    ports:
+      - 8080:80
+    depends_on:
+      - postgres