ci: disable net 20 -3.5 test assemblies when on APPVEYOR
ci: disable net 20 -3.5 test assemblies when on APPVEYOR

tpierrain/NFluent,dupdob/NFluent,tpierrain/NFluent,dupdob/NFluent,NFluent/NFluent,NFluent/NFluent,dupdob/NFluent,tpierrain/NFluent