chore(demo): change button color to make it more obvious

Author: ghiscoding-SE

examples/vite-demo-vanilla-bundle/src/examples/example19.html

@@ -14,7 +14,7 @@ <h5 class="title is-5 mb-3">
   Grid - using <code>enableExcelCopyBuffer</code> which uses <code>SlickCellSelectionModel</code>
 </h5>
 <h6 class="title is-6">
-  <button class="button is-small" onclick.delegate="togglePagination()"
+  <button class="button is-small is-primary" onclick.delegate="togglePagination()"
     data-text="toggle-pagination-btn">
     <span class="icon mdi mdi-swap-vertical"></span>
     <span>Toggle Pagination</span>