message: chore(header): add v3 docs link
diff: @@ -40,6 +40,7 @@ export class DocsHeader {
  <nav class="UtilNav">
  <a href="https://ionicframework.com/support" target="_blank">Support</a>
  <a href="https://ionicframework.com/community" target="_blank">Community</a>
  + <a class="outbound" href="https://ionicframework.com/docs/v3" target="_blank">v3 <Outbound/></a>
  <a class="outbound" href="https://github.com/ionic-team/ionic" target="_blank">GitHub <Outbound/></a>
  </nav>
  </header>
  