Merge pull request #4 from OpenZeppelin/renovate/actions-cache-4.x

Update actions/cache action to v4

.github/setup/action.yml

@@ -11,7 +11,7 @@ runs:
       id: yarn-cache-dir-path
       run: echo "dir=$(yarn cache dir)" >> $GITHUB_OUTPUT
     - name: Restore yarn cache
-      uses: actions/cache@v3
+      uses: actions/cache@v4
       id: cache # use this to check for `cache-hit` (`steps.yarn-cache.outputs.cache-hit != 'true'`)
       with:
         path: ${{ steps.yarn-cache-dir-path.outputs.dir }}