[joss-review] do not install pymultinest to avoid installing mpi4py via conda

[zonca]

In the install instructions:
https://bayeseor.readthedocs.io/en/latest/installation.html

you specify that it is useful to comment out pycuda and mpi4py, it seems you also need to comment out pymultinest, because it depends on multinest which requires mpi:

https://github.com/conda-forge/multinest-feedstock/blob/main/recipe/meta.yaml

[jburba]

Thanks for pointing this out. I've updated the documentation accordingly in #27.