Deleting the Github Source hangs

[mattmoor]

kubectl delete githubsource.sources.eventing.knative.dev/githubsourcesample

It has a finalizer, so I'm guessing this isn't being handled properly.

[mattmoor]

cc @evankanderson @vaikas-google

[mattmoor]

This seems to happen even with --grace-period=0 --force.

I'm sort of at a loss, I'm a little worried about this resource sitting in purgatory and inhibiting my ability to experiment further without razing my cluster.

[mattmoor]

I seem to have been able to delete it by kubectl edit + removing the finalizer. Hopefully this didn't leak anything important :)

[mattmoor]

Now I see a webhook!

[evankanderson]

This looks like a duplicate of knative/eventing#672, which was fixed by knative/eventing-contrib#146.