refactor: Ensure Flask framework leverages the Flask-SQLAlchemy session (Phase II) (#26909)

tests/unit_tests/dao/dataset_test.py

@@ -27,6 +27,7 @@ def test_validate_update_uniqueness(session: Session) -> None:
     In particular, allow datasets with the same name in the same database as long as they
     are in different schemas
     """
+    from superset import db
     from superset.connectors.sqla.models import SqlaTable
     from superset.models.core import Database
 
@@ -46,8 +47,8 @@ def test_validate_update_uniqueness(session: Session) -> None:
         schema="dev",
         database=database,
     )
-    session.add_all([database, dataset1, dataset2])
-    session.flush()
+    db.session.add_all([database, dataset1, dataset2])
+    db.session.flush()
 
     # same table name, different schema
     assert (