Update actions/cache action to v6 (#377)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

.github/workflows/main.yml

@@ -21,7 +21,7 @@ jobs:
           node-version-file: ".nvmrc"
 
       - name: Reuse npm cache folder
-        uses: actions/cache@v5
+        uses: actions/cache@v6
         env:
           cache-name: cache-node-modules
         with: