message: docs(tabs): add aria attributes description
  Closes
diff: -<p>Note that tabs can be given <code class="highlighter-rouge">role="tablist"</code>, <code class="highlighter-rouge">role="tab"</code> and <code class="highlighter-rouge">role="tabpanel"</code> attributes. These are appropriate for tabbed interfaces, as described in the <a href="https://www.w3.org/TR/wai-aria-practices/#tabpanel"><abbr title="Web Accessibility Initiative">WAI</abbr> <abbr title="Accessible Rich Internet Applications">ARIA</abbr> Authoring Practices</a>.</p>
  +<p>Note that tabs can be given <code class="highlighter-rouge">role="tablist"</code>, <code class="highlighter-rouge">role="tab"</code> and <code class="highlighter-rouge">role="tabpanel"</code> attributes.
  + These are appropriate for tabbed interfaces, as described in the <a href="https://www.w3.org/TR/wai-aria-practices/#tabpanel"><abbr title="Web Accessibility Initiative">WAI</abbr>
  + <abbr title="Accessible Rich Internet Applications">ARIA</abbr> Authoring Practices</a>.</p>
  +<p>If your control element is targeting a single collapsible element - you should add the <code>aria-controls</code> attribute to the control element,
  + containing the <code>id</code> of the collapsible element.</p>
  +<p>To confirm the tab content opening you should use <code>aria-selected</code> property.
  + If <code>aria-selected="true"</code> it indicates the tab control is activated and its associated panel is displayed.</p>
  +<p>If you use a visible text element on the page as a label for a focusable element - you should add <code>aria-labelledby</code>. It refers to the tab element that controls the panel.</p>
  