before this change, we rely on the default-generated fmt::formatter
created from operator<<, but fmt v10 dropped the default-generated
formatter.
in this change, `fmt::formatter<>` is added for following classes for
backward compatibility with {fmt} < 10:
* `data_dictionary::no_such_keyspace`
* `data_dictionary::no_such_column_family`
Refs #13245
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>