lint fix

Author: Mikolaj Umanski

src/azure-cli/azure/cli/command_modules/acs/_validators.py

@@ -828,9 +828,11 @@ def validate_disable_windows_outbound_nat(namespace):
             raise ArgumentUsageError(
                 '--disable-windows-outbound-nat can only be set for Windows nodepools')
 
+
 def validate_message_of_the_day(namespace):
     """Validates message of the day can only be used on Linux."""
     if namespace.message_of_the_day is not None and namespace.message_of_the_day != "":
         if namespace.os_type is not None and namespace.os_type != "Linux":
             raise ArgumentUsageError(
-                '--message-of-the-day can only be set for linux nodepools')
+                '--message-of-the-day can only be set for linux nodepools')
+