Minor tweaks to the revision script template to avoid some future linting fixups (#910)

Minor adjustments to the template introduced in #906

Author: bpkroth

mlos_bench/mlos_bench/storage/sql/alembic/script.py.mako

@@ -1,11 +1,17 @@
+#
+# Copyright (c) Microsoft Corporation.
+# Licensed under the MIT License.
+#
 """${message}
 
 Revision ID: ${up_revision}
 Revises: ${down_revision | comma,n}
 Create Date: ${create_date}
 
 """
-from typing import Sequence
+# pylint: disable=no-member
+
+from collections.abc import Sequence
 
 from alembic import op
 import sqlalchemy as sa