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 dht::decorated_key and
repair_sync_boundary.
please note, before this change, repair_sync_boundary was using
the operator<< based formatter of `dht::decorated_key`, so we are
updating both of them in a single commit.
because we still use the homebrew generic formatter of vector<>
in to format vector<repair_sync_boundary> and vector<dht::decorated_key>,
so their operator<< are preserved.
Refs #13245
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
Closesscylladb/scylladb#16994
0cbf8f75f0