Change command for deploying Material for MkDocs

Change the command for deploying Material for MkDocs since I no longer subscribe to Insiders version of Material for MkDocs.

.github/workflows/ci.yml

@@ -29,5 +29,4 @@ jobs:
           key: ${{ runner.os }}-${{ hashFiles('.cache/**') }}
           path: .cache
       - run: pip install -r requirements.txt
-      - run: pip install git+https://${GH_TOKEN}@github.com/squidfunk/mkdocs-material-insiders.git
-      - run: make deploy
+      - run: mkdocs gh-deploy --force