Fix Variable.set rewriting team_name of existing variables (#71823)

Author: ccoliu

airflow-core/src/airflow/models/variable.py

@@ -287,7 +287,6 @@ def set(
                 val=val,
                 description=description,
                 is_encrypted=is_encrypted,
-                team_name=team_name,
             )
             stmt = build_upsert_stmt(
                 get_dialect_name(session), Variable, ["key"], upsert_values, update_fields

airflow-core/tests/unit/models/test_variable.py

@@ -369,6 +369,14 @@ def test_masking_from_db(self, session):
         finally:
             session.rollback()
 
+    @conf_vars({("core", "multi_team"): "True"})
+    def test_variable_set_does_not_change_team_name_on_update(self, testing_team, session):
+        Variable.set(key="k", value="v1", session=session)
+
+        Variable.set(key="k", value="v2", team_name=testing_team.name, session=session)
+
+        assert Variable.get("k") == "v2"
+
     @mock.patch("airflow.models.variable.ensure_secrets_loaded")
     def test_caching_caches(self, mock_ensure_secrets: mock.Mock):
         mock_backend = mock.Mock()