serial_regression_AD.py file comparison for the RHT-CFD Adjoint test

[thomasdick]

Description

The Coupled RHT-CFD Adjoint test in the serial_regression_AD.py is designed to compare the calculated gradient file with a reference.
Yet the routine run_filediff() is never called for this test, only the routine run_test().

I tried to modify the reference file 'of_grad_cd.csv.ref' and checked it on my local machine. The output still shows that the test has passed, even though the calculated gradient file and the reference file are different.

To Reproduce
Change the reference values in the file 'of_grad_cd.csv.ref' and run serial_regression.py.

This might be a bug in this test. Can you check if the test fails in the automated tests if a wrong reference gradient file is used?

Desktop (please complete the following information):

OS: Linux - Fedora
C++ compiler and version: g++ (GCC) 11.2.1
MPI implementation and version: Open MPI
SU2 Version: 7.2.1

Thanks and Best Regards,
Thomas