break long tests up into more functions

[stonecoldhughes]

functionality tests seem to often have 3 distinct sections: a "setup", followed by a "solve", followed by a "validation/comparison" step. If these 3 steps are handled in dedicated functions, it may improve readability and make the flow of control and separation of responsibility more clear.

[pelesh]

CC @kswirydo

[stonecoldhughes]

for the first PR, let's operate on the testSysRefactor.cpp testing file and use the starter template for the functionality test helper