GitLab

* [fix] mypy and flaky test

- CI didn't seem to catch this or maybe I merged incorrectly yesterday
- this should fix the mypy error on master
- also updated a test that seems to be flaky due to tcp port conflict

* another flaky test, hopefully more determinism helps

* CR

* skip 1.6

* fix

* minor
Co-authored-by: Min Xu <min.xu@acm.org>