querier_cache: insert_querier: ignore errors to register inactive reader
querier_cache: insert_querier: ignore errors to register inactive reader

Since the reader may normally dropped upon
registration, hitting an error is equivalent to having
it evicted at any time, so just log the exception
and ignore it.

Signed-off-by: Benny Halevy <23c997c90eb8537635e9392d48e7af1bf1b2ca22@scylladb.com>

scylladb/scylla,scylladb/scylla,scylladb/scylla,scylladb/scylla