message: fix trafficmanager API version directory for Go
diff: @@ -172,7 +172,7 @@ These settings apply only when `--tag=package-2018-03 --go` is specified on the
  Please also specify `--go-sdk-folder=<path to the root directory of your azure-sdk-for-go clone>`.
  ``` yaml $(tag) == 'package-2018-03' && $(go)
  -output-folder: $(go-sdk-folder)/services/trafficmanager/mgmt/2018-03/trafficmanager
  +output-folder: $(go-sdk-folder)/services/trafficmanager/mgmt/2018-03-01/trafficmanager
  ```
  ### Tag: package-2017-09-preview and go
  