update docs-nav

Author: kaitlynmichael

layouts/partials/docs-nav.html

@@ -25,6 +25,7 @@
         </button>
         <div id="versionDropdownKubernetes" class="menu__version-selector__list version-selector-control">
             <a href="{{ absURL "operate/kubernetes/" }}" id="kubernetes-version-select-latest" onclick="_setSelectedVersion('kubernetes', 'latest')">latest</a>
+            <a href="{{ absURL "operate/kubernetes/7.8.4/" }}" id="kubernetes-version-select-7.8.6" onclick="_setSelectedVersion('kubernetes', 'v7.8.6')">v7.8.6</a>
             <a href="{{ absURL "operate/kubernetes/7.8.4/" }}" id="kubernetes-version-select-7.8.4" onclick="_setSelectedVersion('kubernetes', 'v7.8.4')">v7.8.4</a>
             <a href="{{ absURL "operate/kubernetes/7.4.6/" }}" id="kubernetes-version-select-7.4.6" onclick="_setSelectedVersion('kubernetes', 'v7.4.6')">v7.4.6</a> 
         </div>