ix(postgres): randomize test_reader username to prevent CI collisions

Resolves #5972. Appended a random UUID suffix to the Postgres test user creation logic to ensure parallel integration tests are completely isolated and do not collide.

Author: sakshipatil-hue

tests/core/engine_adapter/integration/test_integration_postgres.py

@@ -1,3 +1,4 @@
+import uuid
 import typing as t
 from contextlib import contextmanager
 import pytest
@@ -49,17 +50,15 @@ def create_users(
 
     try:
         for role_name in role_names:
-            user_name = f"test_{role_name}"
-            _cleanup_user(engine_adapter, user_name)
-
-        for role_name in role_names:
-            user_name = f"test_{role_name}"
+            random_suffix = uuid.uuid4().hex[:6]
+            user_name = f"test_{role_name}_{random_suffix}"
+            
             password = random_id()
             engine_adapter.execute(f"CREATE USER \"{user_name}\" WITH PASSWORD '{password}'")
             engine_adapter.execute(f'GRANT USAGE ON SCHEMA public TO "{user_name}"')
+            
             created_users.append(user_name)
             roles[role_name] = {"username": user_name, "password": password}
-
         yield roles
 
     finally: