Update dpage/pgadmin4 Docker tag to v8.11 (#30)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| dpage/pgadmin4 | minor | `8.8` -> `8.11` |

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docker/compose/pgadmin/docker-compose.yml

@@ -1,6 +1,6 @@
 services:
   pgadmin:
-    image: dpage/pgadmin4:8.8
+    image: dpage/pgadmin4:8.11
     container_name: pgadmin
     labels:
       - homepage.group=Relational