Clarify pubsub durability boundary

crates/geth/tests/bootstrap.rs

@@ -1554,6 +1554,7 @@ fn pubsub_pub_sub_uses_lossy_in_memory_runtime() {
             assert_eq!(messages.len(), 1);
             assert_eq!(messages[0].message, "online");
             assert!(note.contains("not authoritative storage"));
+            assert!(note.contains("CAS, KV, documents, or DB resources"));
         }
         other => panic!("unexpected response: {other:?}"),
     }