[RM-7949] useloglambdasampling parameter incompatible with fft continuumfit disabled

Created on 2023-03-09 15:13:04 by Ali Allaoui. % Done: 100

parameter @LineModelSolve.linemodel.useloglambdasampling@ should be set to true only if @ LineModelSolve.linemodel.continuumfit.fftprocessing@ is set to true.

currently the check is not performed since #7924 and thus the code segfaults
see:

• https://gitlab.lam.fr/CPF/cpf-redshift/-/blob/53afacb44e64c31ada50ae31159cf3852e5e5baf/RedshiftLibrary/src/lib/method/linemodelsolve.cpp#L101
• https://gitlab.lam.fr/CPF/cpf-redshift/-/blob/53afacb44e64c31ada50ae31159cf3852e5e5baf/RedshiftLibrary/src/lib/linemodel/linemodelfitting.cpp#L143

TODO:
prevent the segfault by forbidding the incompatible combination. Either throw when using the option in C++ code, and/or validate the parameters.json at the python API level