dev: run server cleanup after run, use stable dir for local use
Created by: bobheadxi
Because we generate a random dir these dirs no longer get cleaned up after the job, and we risk potentially using up a lot of disk.
- tests now configure dirs for buildkite runs, instead of run-server-image
- tests now clean up the target dir before and after the script
- local usage of run-server-image no longer uses a random dir