message: add tags for go sdk release v54.2.0
diff: @@ -13,10 +13,20 @@ go:
  ``` yaml $(go) && $(multiapi)
  batch:
  + - tag: package-2021-03-01
  - tag: package-2017-12-01
  - tag: package-2018-07-12
  ```
  +### Tag: package-2021-03-01 and go
  +
  +These settings apply only when `--tag=package-2021-03-01 --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-2021-03-01' && $(go)
  +output-folder: $(go-sdk-folder)/services/$(namespace)/mgmt/2021-03-01/$(namespace)
  +```
  +
  ### Tag: package-2018-07-12 and go
  These settings apply only when `--tag=package-2018-07-12 --go` is specified on the command line.
  