Assigning to a member of an uninitialized optional
does not initialize the object before assigning to it.
This resulted in the AddressSanitizer detecting attempt
to double-free when the uninitialized string contained
apprently a bogus pointer.
The change emplaces the returned optional when needed
without resorting to the copy-assignment operator.
So it's not suceptible to assigning to uninitialized
memory, and it's more efficient as well...
Fixesscylladb/scylladb#19041
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
(cherry picked from commit b2fa954d82)
Closesscylladb/scylladb#19117
fd7284ec06