Go SDK workflow examples are outdated

The How-to: Manage Workflows article to schedule a new workflow is wrong for Go and need updating in the same way that the Python ones were updated.

The Go Sample should be replaced by the example here https://github.com/dapr/go-sdk/blob/main/examples/workflow/main.go (without the test cases) entirely

Need to also change the names of the APIs in that section from Start to ScheduleNewWorkflow
