add action for building docs on push

.github/workflows/docs.yml

@@ -0,0 +1,15 @@
+name: ci
+on:
+  push:
+    branches:
+      - st4000-exploration
+jobs:
+  deploy:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - uses: actions/setup-python@v2
+        with:
+          python-version: 3.x
+      - run: pip install mkdocs-material
+      - run: mkdocs gh-deploy --force