Deleting the tutorial does not delete the LB it created

[NeckBeardPrince]

This can cause people to be charged for the LB that they thought was deleted.

[timoreimann]

👋 yep you're right, we should fix that. There's a note at the bottom of the README, but cleaning up automatically makes much more sense.

We put the LB ID in an annotation of the Service object. So we can extend our teardown script by doing something like

doctl compute load-balancer delete --force $(kubetl get svc doks-example -o jsonpath="{.metadata.annotations.kubernetes\.digitalocean\.com/load-balancer-id})

Happy for a small contribution, otherwise I'll drive this myself in a free minute.