Modify the github action

.github/workflows/deploy-docs.yml

@@ -11,7 +11,9 @@ jobs:
     steps:
       - name: Checkout master
         uses: actions/checkout@v2
+      - name: Install Mkdocs
+        run: |
+          python -m pip install --upgrade pip
+          pip install mkdocs
       - name: Deploy docs
-        uses: mhausenblas/mkdocs-deploy-gh-pages@nomaterial
-        env:
-          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        run: python -m mkdocs gh-deploy