Automatic merge from submit-queue
fix annotate.go single resource check
```release-note
Fix issue with kubectl annotate when --resource-version is provided.
```
When using `kubectl annotate` with a `--resource-version` on a resource, such as `kubectl annotate pod <pod_name> --resource-version=1820 description='myannotation'`, the command fails with the error: `error: --resource-version may only be used with a single resource`.
Upon printing the output of `resources` that the annotate command receives from cli args, it prints: `Resources:[pod <pod_name>]`. In other words, it treats the name of the resource as a second resource. This PR addresses this issue by using the resource builder `Singular` flag to determine if only a single resource was passed.