See https://deck-ci.apps.ci.l2s4.p1.openshiftapps.com/view/gcs/origin-ci-test/pr-logs/pull/openshift-knative_serverless-operator/336/pull-ci-openshift-knative-serverless-operator-master-4.3-e2e-aws-ocp-43/1273247802448678912

I believe this is due to the Webhooks not being removed correctly. I took a first stab at fixing this by doing some fixes to the uninstall routine. We need to fix this for 1.8.0