docs(toh-5): wrap moduleId prose in Jade block (#3013)

Author: chalin

public/docs/ts/latest/tutorial/toh-pt5.jade

@@ -868,10 +868,11 @@ block css-files
 
     +makeExcerpt('app/app.component.ts (active router links)', 'template')
 
-:marked
-  First add `moduleId: module.id` to the `@Component` metadata of the `AppComponent`
-  to enable _module-relative_ file URLs.
-  Then add a `styleUrls` property that points to this CSS file as follows.
+block style-urls
+  :marked
+    First add `moduleId: module.id` to the `@Component` metadata of the `AppComponent`
+    to enable _module-relative_ file URLs.
+    Then add a `styleUrls` property that points to this CSS file as follows.
 
 +makeExcerpt('app/app.component.ts','styleUrls')