Revert "Reenable scratchspace (debug)"

This reverts commit 15abddb.

Author: blegat

.github/workflows/ExportPluto.yaml

@@ -39,6 +39,7 @@ jobs:
               uses: julia-actions/cache@v2
               with:
                 cache-registries: "true"
+                cache-scratchspaces: "false"
 
             # We set up a folder that Pluto can use to cache exported notebooks. If the notebook file did not change, then Pluto can take the exported file from cache instead of running the notebook.
             - name: Set up notebook state cache