Revising tests after cleanup

[zhang-alvin]

The following tests were turned off as they depended on large file sizes (>100kB):

1MB proteus/tests/STLBlocks.stl
proteus/tests/test_spatialtools.py::TestShapeDomainBuilding::test_BC_flags
proteus/tests/test_spatialtools.py::TestShapeDomainBuilding::test_assemble_domain
proteus/tests/test_spatialtools.py::TestShapeDomainBuilding::test_create_shapes

400kB proteus/tests/TwoPhaseFlow/comparison_files/comparison_fillingTank_velocity_t2.csv
proteus/tests/TwoPhaseFlow/test_TwoPhaseFlow.py::TestTwoPhaseFlow::test_fillingTank

20MB proteus/tests/amg_tests/import_modules/saddle_point_mat_1
1MB proteus/tests/amg_tests/import_modules/bcw_matrix_1
proteus/tests/amg_tests/test_amg_methods.py::test_amg_iteration_matrix_1
proteus/tests/amg_tests/test_amg_methods.py::test_amg_iteration_matrix_2

1.3MB proteus/tests/solver_tests/import_modules/saddle_point_matrix.bin
9MB proteus/tests/solver_tests/import_modules/rans2p_step_newton_1.bin
21 MB proteus/tests/solver_tests/import_modules/rans2p_step_newton_5.bin
proteus/tests/solver_tests/test_iterative_methods.py::test_amg_iteration_performance
proteus/tests/solver_tests/test_iterative_methods.py::test_amg_step_problem_01
proteus/tests/solver_tests/test_iterative_methods.py::test_amg_step_problem_02

500kB NSE_cavity_matrix.bin
5MB NSE_step_no_slip.bin
proteus/tests/solver_tests/test_iterative_methods.py::test_Schur_Sp_solve_global_null_space
proteus/tests/solver_tests/test_iterative_methods.py::test_Schur_Sp_solve

185kB proteus/tests/solver_tests_slow/comparison_files/comparison_drivenCavityStokes_velocity_t1.csv
proteus/tests/solver_tests_slow/test_stokesDC_TH_2D.py::TestStokes::test_01_FullRun
proteus/tests/solver_tests_slow/test_stokesDC_TH_2D.py::TestStokes::test_02_FullRun

They need to be reworked so that the dependencies are smaller.