Regression testing does not exit

[MacroLens]

When running regression tests using the provided tests:

python3 tests/regression/regressionTest.py athena

Athena does not quit after loading a test. It looks like the python script tests/regression/regressionTest.py just tries to load each file like:

         cmd = athena_executable + ' ' + input_file + ' quit > ' + res_file

But the quit command line argument doesn't do anything when built with MLTON.
This will halt on the first test file loaded and will not continue.

Additionally having no Athena installation results in the regression testing passing with zero errors, which is not good. Reproducible by cloning on any machine that has no athena installation and running

python3 tests/regression/regressionTest.py
.
.
.
Total number of errors: 0, all output found in /path/to/regression_results.txt.