Fix missing comma in error handler

Author: alandmoore

Chapter09/coffee_list1.py

@@ -67,7 +67,7 @@ def __init__(self):
         missing_tables = required_tables - set(tables)
         if missing_tables:
             qtw.QMessageBox.critical(
-                None, 'DB Integrity Error'
+                None, 'DB Integrity Error',
                 'Missing tables, please repair DB: '
                 f'{missing_tables}')
             sys.exit(1)