To run this, you can try:
curl -ks https://gist.githubusercontent.com/PCreations/6df8b04cbf68c10a9b3c/raw/445b87d1d4550b336353cec77720502fd6f42022/uninstall-node.sh | bash
I haven't tested this script doing it this way but i run a lot of my Gists like this so maybe this one'll work too.
Alternatively,
curl -ksO https://gist.githubusercontent.com/PCreations/6df8b04cbf68c10a9b3c/raw/445b87d1d4550b336353cec77720502fd6f42022/uninstall-node.sh
chmod +x ./uninstall-node.sh