edit yaml cache-version

Author: duncanobrien

.github/workflows/R-CMD-check.yaml

@@ -42,7 +42,7 @@ jobs:
 
       - uses: r-lib/actions/setup-r-dependencies@v1
         with:
-          cache: false
+          cache-version: 2
           extra-packages: rcmdcheck
 
       - uses: r-lib/actions/check-r-package@v1