Revert "Narrow the cache of xdg directory" (#22)

Reverts #20

This results in the `~/.cache` directory gets created under `root`
instead of `runner`. Reverting fix this problem.

Verified the fix with
#21

Author: LucilleH

action.yml

@@ -122,8 +122,7 @@ runs:
       uses: actions/cache@v3
       with:
         path: |
-          ~/.cache/devbox
-          ~/.cache/nix
+          ~/.cache
           ~/.local/state/nix
           ~/.nix-defexpr
           ~/.nix-profile