nc not there, install first

.github/workflows/nightly.yml

@@ -35,6 +35,8 @@ jobs:
           echo 127.0.0.1 api.notion.com >> /etc/hosts
       - name: Start a dummy server listening on 443
         run: |
+          apt update
+          apt install -y netcat
           while true; do
             echo "HTTP/1.1 200 OK\\n\\nHello from dummy server" | nc -l -p 443 -q 1
           done