Add Updating Bazel back into navigation
Closes
<li><a href="/versions/{{ current_version }}/versioning.html">Release Versioning</a></li>
<li><a href="/versions/{{ current_version }}/releases.html">Release Policy</a></li>
<li><a href="/versions/{{ current_version }}/backward-compatibility.html">Backward Compatibility</a></li>
+ <li><a href="/versions/{{ current_version }}/updating-bazel.html">Updating Bazel</a></li>
<li>
<a class="sidebar-nav-heading" data-toggle="collapse"
href="#release-notes-menu" aria-expanded="false"
