chore(deps): update actions/cache action to v2.1.6 (#849)

Author: renovate[bot]

.github/workflows/nodejs.yml

@@ -26,7 +26,7 @@ jobs:
         id: yarn-cache
         run: echo "::set-output name=dir::$(yarn config get cacheFolder)"
 
-      - uses: actions/[email protected].5
+      - uses: actions/[email protected].6
         with:
           path: ${{ steps.yarn-cache.outputs.dir }}
           key: yarn2-${{ hashFiles('yarn.lock') }}