message: fix(docs-infra): correctly style the CLI version in code snippet
  Some CLI versions (such as `@next`) are not parsed (and thus not
  formatted) correctly in code snippets. Fix this by explicitly adding an
  appropriate CSS class to the `<aio-angular-dist-tag>` elements to let
  PrettyPrint know how to style this token.
  PR Close
diff: @@ -43,7 +43,7 @@ To install the Angular CLI, open a terminal window and run the following command
  <code-example format="shell" language="shell">
  -npm install -g &commat;angular/cli<aio-angular-dist-tag></aio-angular-dist-tag>
  +npm install -g &commat;angular/cli<aio-angular-dist-tag class="pln"></aio-angular-dist-tag>
  </code-example>
  