[THM] Removed the parameter documentation of the deleted variables

...sses/process/THERMO_HYDRO_MECHANICS/t_biot_coefficient.md

...ocesses/process/THERMO_HYDRO_MECHANICS/t_fluid_density.md

.../THERMO_HYDRO_MECHANICS/t_fluid_specific_heat_capacity.md

...ss/THERMO_HYDRO_MECHANICS/t_fluid_thermal_conductivity.md

...esses/process/THERMO_HYDRO_MECHANICS/t_fluid_viscosity.md

...ANICS/t_fluid_volumetric_thermal_expansion_coefficient.md

...rocess/THERMO_HYDRO_MECHANICS/t_intrinsic_permeability.md

...rj/processes/process/THERMO_HYDRO_MECHANICS/t_porosity.md

...ocesses/process/THERMO_HYDRO_MECHANICS/t_solid_density.md

...MECHANICS/t_solid_linear_thermal_expansion_coefficient.md

.../THERMO_HYDRO_MECHANICS/t_solid_specific_heat_capacity.md

...ss/THERMO_HYDRO_MECHANICS/t_solid_thermal_conductivity.md

...sses/process/THERMO_HYDRO_MECHANICS/t_specific_storage.md