Update actions/cache action to v2 (#41)

Co-authored-by: Renovate Bot <[email protected]>

Author: renovate[bot]

.github/workflows/ci.yml

@@ -27,7 +27,7 @@ jobs:
         uses: actions/checkout@master
 
       - name: cache node_modules
-        uses: actions/cache@v1
+        uses: actions/cache@v2
         with:
           path: node_modules
           key: ${{ matrix.os }}-node-v${{ matrix.node }}-deps-${{ hashFiles(format('{0}{1}', github.workspace, '/yarn.lock')) }}