Eventlistener container crashes with eventlistener created with SA having no permissions to use eventlisteners.

[sravankumar777]

Expected Behavior

• Eventlistener shoud log error message & not crash, when event listener is created with a serviceaccount not having permissions for eventlisteners objects.
• Eventlistener could hang-in failure state provided with error message to check for right permissions of serviceaccount.

Actual Behavior

Event Listener container crashes, when an eventlistener created with invalid(serviceaccount) & fired a bitbucket event to check for working condition with eventlistener service url.

Steps to Reproduce the Problem

1. Create EventListener with an invalid serviceaccount(not have permissions for serviceaccount to use eventlistener objects).
2. Using event listener service url, fire an event from any git repository(in this case, i have used bitbucket repository).
3. Check for eventlistener logs in that particular namespace.

Additional Info

EventListener Logs:

{"level":"fatal","logger":"eventlistener","caller":"sink/sink.go:73","msg":"Error getting EventListener tekton-cnb-el in Namespace test-namespace: eventlisteners.triggers.tekton.dev \"tekton-cnb-el\" is forbidden: User \"system:serviceaccount:test-namespace:tenant-pipeline-default\" cannot get resource \"eventlisteners\" in API group \"triggers.tekton.dev\" in the namespace \"test-namespace\"","knative.dev/controller":"eventlistener","stacktrace":"github.com/tektoncd/triggers/pkg/sink.Sink.HandleEvent\n\tgithub.com/tektoncd/triggers/pkg/sink/sink.go:73\nnet/http.HandlerFunc.ServeHTTP\n\tnet/http/server.go:2012\nnet/http.(*ServeMux).ServeHTTP\n\tnet/http/server.go:2387\nnet/http.serverHandler.ServeHTTP\n\tnet/http/server.go:2807\nnet/http.(*conn).serve\n\tnet/http/server.go:1895"}

$ kubectl -n tekton-pipelines get deployments tekton-triggers-controller -ojsonpath='{.metadata.labels.triggers\.tekton\.dev\/release}'
v0.8.0

[sravankumar777]

/kind bug