Add Github Action to build and deploy docs

.github/workflows/deploy-docs.yml

@@ -0,0 +1,47 @@
+name: Build and deploy docs
+
+on:
+  push:
+    branches: [ master, develop ]
+  pull_request:
+    branches: [ master, develop ]
+  workflow_dispatch:
+
+jobs:
+  build:
+
+    runs-on: ubuntu-latest
+
+    steps:
+    - name: Set up Python
+      uses: actions/setup-python@v2
+      with:
+        python-version: '3.8'
+    - name: Clone ns-3
+      run: git clone https://gitlab.com/nsnam/ns-3-dev
+    - uses: actions/checkout@v2
+      with:
+        path: 'ns-3-dev/src/lorawan'
+    - name: Install dependencies needed to generate docs
+      run: |
+        sudo apt-get update
+        sudo apt-get install dia doxygen sphinx-doc sphinx-common python3-pydot texlive-full latexmk dvipng texlive-font-utils
+        sudo mv /etc/ImageMagick-7/policy.xml /etc/ImageMagick-7/policy.xml.bak
+    - name: Build docs
+      run: |
+        cd ns-3-dev/
+        cp utils/.ns3rc ./
+        sed -i "s/all_modules/lorawan/" .ns3rc
+        sed -i "s/False/True/" .ns3rc
+        ./ns3 configure
+        ./ns3 docs all
+    - name: Pushes to another repository
+      uses: cpina/github-action-push-to-another-repository@main
+      env:
+          API_TOKEN_GITHUB: ${{ secrets.API_TOKEN_GITHUB }}
+      with:
+          source-directory: 'docs/'
+          destination-github-username: 'signetlabdei'
+          destination-repository-name: 'lorawan-docs'
+          user-email: [email protected]
+          target-branch: master