Refactor account models to use SQLAlchemy 2.0 dataclass mapping (#26415)

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api/tests/unit_tests/repositories/workflow_node_execution/test_sqlalchemy_repository.py

@@ -59,12 +59,11 @@ def session():
 @pytest.fixture
 def mock_user():
     """Create a user instance for testing."""
-    user = Account()
+    user = Account(name="test", email="test@example.com")
     user.id = "test-user-id"
 
-    tenant = Tenant()
+    tenant = Tenant(name="Test Workspace")
     tenant.id = "test-tenant"
-    tenant.name = "Test Workspace"
     user._current_tenant = MagicMock()
     user._current_tenant.id = "test-tenant"