if the endpoint specified when creating a KEYSPACE is not found,
when flushing a memtable, we would throw an `std::out_of_range`
exception when looking up the client in `storage_manager::_s3_endpoints`
by the name of endpoint. and scylla would crash because of it. so
far, we don't have a good way to error out early. since the
storage option for keyspace is still experimental, we can live
with this, but would be better if we can spot this error in logging
messages when testing this feature.
also, in this change, `std::invalid_argument` is thrown instead of
`std::out_of_range`. it's more appropriate in this circumstance.
Refs #15074
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
Closes#15075
86e8be2dcd