* ds-querier: handle execute errors better
* fix: change how GetResponseCode works to return 418 if rsp is nil
418 is a bit of an easter egg which in this case works since we don't
have an rsp but we do know something went wrong, so a 200 won't work.
Also changed this to return the code in the frame, not sure why we
weren't.
* tests: fix GetResponseCode tests
* log no rsp case
* bring back og error log
