Update gh-pages.yml

Author: simongravelle

.github/workflows/gh-pages.yml

@@ -37,6 +37,7 @@ jobs:
           make clean
           make html
           cp source/index_replace.html build/html/index.html
+          cp source/lammps_replace.html build/html/non-tutorials/lammps.html
       - name: Deploy
         uses: peaceiris/actions-gh-pages@v3
         if: ${{ github.ref == 'refs/heads/version2.0' }}