PartiallyOrderedSetTest#testPosetBitsLarge is quite large, and it performs exactly the same computation during test execution.
I suggest to guard the test like testPosetBitsLarge2 with ENABLE_SLOW:
Alternative options: reduce test complexity to make it faster, and/or randomize test execution so it explores new test cases on every execution. For instance, it could run for 5 seconds and explore new cases each time.
Current test is more or less useless, and it does take noticeable CI time.