Remove correct line in nightly (#82)

Author: lucacome

.github/workflows/ci.yml

@@ -40,7 +40,7 @@ jobs:
         if: (github.event_name == 'schedule')
         run: |
           sed -i 's|pkgs.nginx.com|pkgs-test.nginx.com|g' docker/Dockerfile
-          sed -i '15d' docker/Dockerfile
+          sed -i '16d' docker/Dockerfile
           sed -i "16i && sed -i 's|pkgs|pkgs-test|g' /etc/apt/apt.conf.d/90pkgs-nginx \\\ " docker/Dockerfile
           sed -i 's|deb https|deb [trusted=yes] https|g' docker/Dockerfile
           sed -i 's|nginx-plus-\${{ env.NGINX_PLUS_VERSION }}|nginx-plus|g' docker/Dockerfile