message: Add examples for all StateLabel variants
diff: @@ -7,6 +7,11 @@ Use StateLabel components to show the status of an issue or pull request.
  ```jsx live
  <StateLabel status="issueOpened">Open</StateLabel>
  +<StateLabel status="issueClosed">Closed</StateLabel>
  +<StateLabel status="pullOpened">Open</StateLabel>
  +<StateLabel status="pullClosed">Closed</StateLabel>
  +<StateLabel status="pullMerged">Merged</StateLabel>
  +<StateLabel status="draft">Draft</StateLabel>
  ```
  ## System props
  