[test][multidomain][boundary][stokesdarcy][1p2c_1p2c] choose which properties files to use

For the test [test][multidomain][boundary][stokesdarcy][1p2c_1p2c] there are two properties files (properties.hh and one free-flow specific properties_stokes.hh).

Problem:

• only properties.hh(for stokes and darcy) is currently used, but properties_stokes.hh exists also

Question:

• Should properties.hh still be used? If so, properties_stokes.hh should be deleted.
• Or should domain specific properties files (properties_stokes.hh and properties_darcy.hh) be used? If so, properties_darcy.hh should be added, properties_stokes.hh and properties_darcy.hh should included in main.cc and moreover properties.hh should be deleted