chore: add support for multiline annotations in the API

tools/api-builder/angular.io-package/templates/class.template.html

@@ -76,7 +76,7 @@ div(layout="row" layout-xs="column" class="row-margin ng-cloak")
   div(flex="80" flex-xs="100")
     {%- for decorator in doc.decorators %}
       pre.prettyprint.no-bg
-        code(class="api-doc-code")
+        code(class="api-doc-code").
           @{$ decorator.name $}{$ paramList(decorator.arguments) | indent(10, false) $}
       :marked
       {%- if not decorator.notYetDocumented %}