message: Fix typo in readme.go for web
diff: @@ -24,7 +24,7 @@ batch:
  These settings apply only when `--tag=package-2019-08 --go` is specified on the command line.
  Please also specify `--go-sdk-folder=<path to the root directory of your azure-sdk-for-go clone>`.
  -``` yaml $(tag) == 'package-2018-02' && $(go)
  +``` yaml $(tag) == 'package-2019-08' && $(go)
  output-folder: $(go-sdk-folder)/services/$(namespace)/mgmt/2019-08-01/$(namespace)
  ```
  