refactor(db): use Dialect instead of Engine in select_star to avoid SSH tunnels (#35540)

Co-authored-by: Claude <noreply@anthropic.com>

tests/unit_tests/db_engine_specs/test_bigquery.py

@@ -154,13 +154,12 @@ def test_select_star(mocker: MockerFixture) -> None:
         query.compile(dialect=BigQueryDialect(), compile_kwargs={"literal_binds": True})
     )
 
-    engine = mocker.MagicMock()
-    engine.dialect = BigQueryDialect()
+    dialect = BigQueryDialect()
 
     sql = BigQueryEngineSpec.select_star(
         database=database,
         table=Table("my_table"),
-        engine=engine,
+        dialect=dialect,
         limit=100,
         show_cols=True,
         indent=True,