* add coverage report

* define env vars in shared action

* reduce time for longest running tests

* fix broken shared action

* reduce test time

* reducing Pipeline test times

* further reducing test times

* rework Z3 test

* testing new mp.pool and persistent dist envs

* fix import

* reuse distributed environment for tests with lots of param combos

* fix for dist teardown

* fix pickling issue with pool cache

* actually fix pickling problem

* avoid running pool cache stuff on non-distributed tests

* fix issues with nested mp.pool

* fix for nested pools in Pipeline Engine

* re-add params

* update workflows with pytest opts

* implement feedback

* resolve race condition with port selection

* Update tests/unit/common.py

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Co-authored-by: NOlatunji Ruwase <olruwase@microsoft.com>