Remove ParallelTestRunner in favor of serial tests

[odow]

This works around some intermittent segfaults we are seeing with HiGHS on Julia v1.10.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 99.64%. Comparing base (5cfef38) to head (9f5c6bd).
⚠️ Report is 1 commits behind head on master.

Additional details and impacted files

@@           Coverage Diff           @@
##           master     #211   +/-   ##
=======================================
  Coverage   99.64%   99.64%           
=======================================
  Files          15       15           
  Lines        1424     1426    +2     
=======================================
+ Hits         1419     1421    +2     
  Misses          5        5           

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[odow]

@filikat and @Opt-Mucca, here's another:

No parallelism in Julia this time, so it must be some issue in HiGHS. I'll see if I can reproduce locally.

[odow]

I have not been able to reproduce locally. But here is a nicer stack-trace:

This one flags the profiling code.

[odow]

Here's another one:

[odow]

Here's a bit more information:

[filikat]

The last two involve the parallel scheduler during the MIP solve.
It would be good if we could reproduce locally. Do you know which problems fail @odow? Is it always the same?

[odow]

No it’s always in different parts of the tests

[odow]

Moving this to ERGO-Code/HiGHS#3136 instead.