Update ceph-windows-test job

Update ceph-windows-test job

* Create `scripts/ceph-windows` directory with the common scripts
  for the Ceph Windows testing.
* Move `run_tests` script to `scripts/ceph-windows`.
* Remove VM image caching from the `run_tests` script.
* Add `cleanup_tests` script to `scripts/ceph-windows`, and call
  this as a post-build step when the job is aborted.
* Add `get_chacra_build` build script, and refactor away this logic
  from the `run_tests` script.
* Move cleanup Windows tests function to `scripts/build_utils.sh`.