Test to deploy documentation HTML to dedicated branch

.github/workflows/publish.yml

@@ -35,6 +35,11 @@ jobs:
         uses: actions/upload-pages-artifact@v1
         with:
           path: "_build"
+      - name: Upload build folder
+        uses: actions/upload-artifact@v3
+        with:
+          name: build-folder
+          path: "_build"
 
   deploy-documentation:
     runs-on: ubuntu-latest
@@ -48,4 +53,27 @@ jobs:
     steps:
       - name: Deploy to GitHub pages
         id: deployment
-        uses: actions/deploy-pages@v2
+        uses: actions/deploy-pages@v2
+
+  deploy-documentation-branch:
+    runs-on: ubuntu-latest
+    needs: build-documentation
+    steps:
+    - name: Checkout repository
+      uses: actions/checkout@v3
+
+    - name: Set Git config
+      run: |
+          git config --local user.email "[email protected]"
+          git config --local user.name "Github Actions"
+    - name: Create git subtree
+      run: git subtree add --prefix _build origin docportal
+
+    - name: Download build folder
+      uses: actions/download-artifact@v3
+      with:
+        name: build-folder
+        path: _build
+
+    - name: Commit
+      run: git add _build && git commit -m "build - production deploy" && git subtree push --prefix _build origin docportal