Automatic merge from submit-queue (batch tested with PRs 52007, 52196, 52169, 52263, 52291)

[fluentd-gcp addon] Update event-exporter to address metrics problem

Follow-up of https://github.com/GoogleCloudPlatform/k8s-stackdriver/pull/37:

```
In the clusters with CA, the number of metric streams will continuously grow if the host is included.
```

Name is updated b/c otherwise addon manager will not be able to pick up the change.