row_cache: Fix undefined behavior in read_wide()
row_cache: Fix undefined behavior in read_wide()

_underlying is created with _range, which is captured by
reference. But range_and_underlyig_reader is moved after being
constructed by do_with(), so _range reference is invalidated.

Fixes #2377.
Message-Id: <f7c67dab5e4c0676c1906c25ea414bb059d20f2d@scylladb.com>

scylladb/scylla,scylladb/scylla,scylladb/scylla,duarten/scylla,avikivity/scylla,duarten/scylla,avikivity/scylla,scylladb/scylla,avikivity/scylla,duarten/scylla