With this MR, all test cases etc should be adapted to the new API. Since all test cases are touched anyway some adaptions are made additionally. The vast majority is just formatting and removing for loops over parameter sets completely to replace it with the pytest functionality. A larger change is the removal of the serial scenarios since these used the LBM module of waLBerlas python coupling. However, this module is removed for almost a year now.
Furthermore, the broken elementwise multiplication from SymPy is removed (https://github.com/sympy/sympy/issues/22353).
Further changes:
_get_relaxation_info_dict function which defines how relaxation rates are set for all methods.