* [ws-manager] Do not delete ghost workspace on start
* [ws-scheduler] Enable asynchronous binding of pods
* [ws-scheduler] Introduce ghosts
- remove a ghost before binding a regular workspace
- make ghosts "invisible" to strategy
* [scheduler] Wait longer on ghost deletion to prevent OOM errors
* [scheduler] Make isRegularWorkspace -> makeGhostsInvisible explicit
* [scheduler] cancel ghost.Delete if it takes too long (5s)
* [ws-scheduler] Add tests for ghost-sepcific state computation
* [scheduler] Make sure ghost are only selected for deletion once
* [scheduler] delete ghosts: ctxDeleteTimeout > gracePeriod
* [scheduler] Don't bind terminated pods
* [scheduler] Make all non-ghost workspaces replace ghosts
* [scheduler] review comments
