github action to build pdf

.github/workflows/gen_pdf.yml

@@ -0,0 +1,23 @@
+name: Generate PDF
+
+on:
+  push:
+    branches:
+      - main
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v2
+
+      - name: Set up LaTeX
+        run: |
+          sudo apt-get update
+          sudo apt-get install -y texlive-full
+
+      - name: Build PDF
+        run: |
+          make