Use libgridxc 2.0.2 in submodule/fetch mode to fix grid issue in vdw calculations

Use libgridxc 2.0.2 in submodule/fetch mode

This fixes an issue with the reparametrized atomic grid when vdw functionals were used. The tolerance for detection of a logarithmic grid has been made looser in libgridxc (see logs there).

The only change is the reference to the libgridxc version used in submodule/fetch modes of building. In the 'fetch' information, the actual libgridxc tag (2.0.2), rather than just the branch name, is now used, to make it exactly compatible with the submodule reference.

Updated also the install_deps.bash script in Tools.

(cherry picked from commit e08de932)