Try automatically deploying the documentation.

Assuming I understood GitHub's documentation correctly, this should
automatically deploy the Maven-built website to
incatools.github.io/odk/robot-plugin/.

Author: gouttegd

.github/workflows/docs.yml

@@ -0,0 +1,35 @@
+name: Build and publish the documentation
+
+on:
+  push:
+    branches: [ "main" ]
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v4
+    - name: Set up JDK 17
+      uses: actions/setup-java@v4
+      with:
+        java-version: '17'
+        distribution: 'temurin'
+        cache: maven
+    - name: Build the site
+      run: mvn -B site
+    - name: Upload the site for publication
+      id: deployment
+      uses: actions/upload-pages-artifact@v3
+      with:
+        path: target/site/
+
+  deploy:
+    environment:
+      name: github-pages
+      url: ${{ steps.deployment.outputs.page_url }}
+    runs-on: ubuntu-latest
+    needs: build
+    steps:
+      - name: Deploy the site
+        id: deployment
+        uses: actions/deploy-pages@v4