[TASK] (import_Seitosh): discard contrib/aff/tests
Code in contrib/aff/tests is not required as part of Seitosh. However, the test code requires additional settings like proper interlanguage linking (C++ and Fortran). To reduce the constraints on the installation environment, discard the subdirectory tests in contrib/aff entirely, as well as all references to the test code made in the Makefile.