Workflow to build the R cached packages on Graham (or any other cluster)

# problem description

The workflow to build the cache directory used for the `renv` environmental manager must be clarified that is currently missing. For the GWF project, the cache directory is located in the following path:
```console
/project/rpp-kshook/Climate_Forcing_Data/assets/r-envs/exact-extract-env/
```

The workflow to build that cache directory is missing.