Function build_no_rows_response 

fn build_no_rows_response(kind: &MutationKind) -> ExecuteResponse

Build the response returned when no rows matched the selection.

Bug-compatible with the coordinator path, which evaluates RETURNING over the diffs and so reports a plain row count when there are none. Postgres returns an empty result set for a zero-row INSERT ... RETURNING instead, but changing that is a change to the path that ships today, not to this one.