Merge pull request #524 from readchina/dependabot/github_actions/acti…

…ons/cache-3

chore(deps): bump actions/cache from 2 to 3

.github/workflows/ci.yml

@@ -21,7 +21,7 @@ jobs:
       - name: Install Python dependencies
         run: python -m pip install --upgrade pip
       - name: Use pip Cache  
-        uses: actions/cache@v2
+        uses: actions/cache@v3
         with:
           path: ~/.cache/pip
           key: ${{ runner.os }}-pip-${{ hashFiles('**/requirements.txt') }}