Refactor GitHub Actions workflow to install LaTeX dependencies and build document directly, updating artifact upload step

.github/workflows/main.yml

@@ -16,7 +16,7 @@ jobs:
       - name: Set up Git repository
         uses: actions/checkout@v4.2.2
 
-      - name: Install LaTeX
+      - name: Install MiKTeX
         run: |
           curl -fsSL https://miktex.org/download/key | tee /usr/share/keyrings/miktex-keyring.asc > /dev/null
           echo "deb [signed-by=/usr/share/keyrings/miktex-keyring.asc] https://miktex.org/download/ubuntu jammy universe" | sudo tee /etc/apt/sources.list.d/miktex.list