fix: add title attribute to table-of-contents links

Synced with origin change that adds tooltip support for truncated TOC items

Author: lacolaco

adev-ja/shared-docs/components/table-of-contents/table-of-contents.component.html

@@ -9,7 +9,7 @@ <h2 class="docs-title">目次</h2>
       <li class="docs-faceted-list-item" [class.docs-toc-item-h2]="item.level === TableOfContentsLevel.H2"
         [class.docs-toc-item-h3]="item.level === TableOfContentsLevel.H3">
         <!-- Not using routerLink + fragment because of: https://github.com/angular/angular/issues/30139 -->
-        <a [href]="location.path() + '#' + item.id" [class.docs-faceted-list-item-active]="item.id === activeItemId()">
+        <a [href]="location.path() + '#' + item.id" [class.docs-faceted-list-item-active]="item.id === activeItemId()" [title]="item.title">
           {{ item.title }}
         </a>
       </li>