[ticket/13180] Increase dateformat field size

remove empty line as marc1706 guided

PHPBB3-13180

phpBB/phpbb/db/migration/data/v31x/increase_size_of_dateformat.php

@@ -32,5 +32,4 @@ class increase_size_of_dateformat  extends \phpbb\db\migration\migration
 			),
 		);
 	}
-
 }