Removed unneccessary installs in GH action (#4)

Author: stefonarch

.github/workflows/deploy-material.yml

@@ -25,7 +25,5 @@ jobs:
           restore-keys: |
             mkdocs-material-
       - run: pip install mkdocs-material
-      - run: pip install mkdocs-exclude
-      - run: pip install pymdown-extensions
       - run: ./update-wikis
       - run: cd docs/ && mkdocs gh-deploy --force