cc @cgenie

After merging 95f311fb , the project doesn't build cleanly on my Mac anymore, in particular:

• llvm-hs-12 won't install anymore (but that might be unrelated, more a general issue in our nix setup);
• Building gargantext-graph segfaults -- I have traced this in the past as one particular botched version of eigen, that your commit is bumping.

I can see if I do some fixup on my side, but is there any reason why we had to upgrade all those deps? Can we revert that commit at all?