chore: add expansion panel to prerender check (#6166)

* Adds the expansion panel to the universal app that will be validated on the CI.

Author: devversion

src/universal-app/kitchen-sink/kitchen-sink.html

@@ -211,3 +211,13 @@ <h2>Tooltip</h2>
 
 <h2>Autosize textarea</h2>
 <textarea mdTextareaAutosize mdAutosizeMaxRows="10"></textarea>
+
+<h2>Expansion Panel</h2>
+<md-expansion-panel>
+  <md-expansion-panel-header>
+    <mat-panel-description>This is a panel description.</mat-panel-description>
+    <mat-panel-title>Panel Title</mat-panel-title>
+  </md-expansion-panel-header>
+  This is the content text that makes sense here.
+  <md-action-row>Action</md-action-row>
+</md-expansion-panel>

src/universal-app/kitchen-sink/kitchen-sink.ts

@@ -8,6 +8,7 @@ import {
   MdChipsModule,
   MdDatepickerModule,
   MdDialogModule,
+  MdExpansionModule,
   MdGridListModule,
   MdIconModule,
   MdInputModule,
@@ -67,6 +68,7 @@ export class KitchenSink { }
     MdTabsModule,
     MdToolbarModule,
     MdTooltipModule,
+    MdExpansionModule
   ],
   bootstrap: [KitchenSink],
   declarations: [KitchenSink],