Parallelize tests

[rahulsom]

This will use all available cores to run tests, and parallelize by all - suite/class/method. On machines with multiple cores, this will vastly improve test performance. These times are on my M1 MBP with 10 (8P + 2E) cores. They were reported by maven on running mvn verify.

I first ran mvn verify and ignored the time.
Then I ran it thrice without this change, and thrice with this change.

All times in seconds.

	Run 1	Run 2	Run 3	Average
Before	253	253	253	253
After	102	101	101	101
Savings				152
%				60

Testing done

All existing tests run

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[MarkEWaite]

Thanks!