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, we define formatters for
* clustering_row::printer
* static_row::printer
* partition_start
* partition_end
* mutation_fragment::printer
and drop their operator<<:s
Refs #13245
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>