Revert "Closes #258. Remove use_transport flag"

[BBArrosDias]

Reverts #259

The Build / build_mac tests have failed.

@mgoodson-cvd do you have a Mac?

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 71.65%. Comparing base (bc221f4) to head (3bb3a5f).
Report is 1 commits behind head on master.

Additional details and impacted files

@@           Coverage Diff           @@
##           master     #267   +/-   ##
=======================================
  Coverage   71.65%   71.65%           
=======================================
  Files         135      135           
  Lines        9089     9089           
=======================================
  Hits         6513     6513           
  Misses       2576     2576           

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

[mgoodson-cvd]

No, but this same issue also affects #265; see this comment. My guess is that it is this line; it probably needs a tolerance on this check. I actually had to do this myself when compiling M++ with old Intel 2018 compilers. I changed it to:

CHECK(model.relaxationTime(mix) == Approx(tau_mw + tau_park).epsilon(tol));

with const double tol = 100*std::numeric_limits<double>::epsilon();. (Maybe could even be constexpr? Didn't try).

Again, I don't have a Mac, so I can't test my hypothesis. I would suggest making this change and re-running pipeline before reverting the merge. There is nothing wrong with the merge itself, as it doesn't affect the M-W code at all. I can make a PR with this change if you'd like, that will trigger a pipeline, and if it passes, then we're good.