fixup! update SQLAlchemy from 1.4 to 2.0

waiverdb/migrations/versions/ce8a1351ecdc_change_subject_to_json.py

@@ -15,15 +15,16 @@
 from sqlalchemy import Text, text
 from sqlalchemy.dialects.postgresql import JSON
 from waiverdb.models.base import json_serializer
+from waiverdb.models import db
 
 
 def upgrade():
     # Re-serialize all subject values to ensure they match the new, consistent
     # serialization we are using.
     connection = op.get_bind()
-    for row in connection.execute('SELECT id, subject FROM waiver'):
+    for row in db.session.execute(text('SELECT id, subject FROM waiver')):
         fixed_subject = json_serializer(json.loads(row['subject']))
-        connection.execute(text('UPDATE waiver SET subject = :subject WHERE id = :id'),
+        db.session.execute(text('UPDATE waiver SET subject = :subject WHERE id = :id'),
                            subject=fixed_subject, id=row['id'])
 
     op.drop_index('ix_waiver_subject')