Fix on source

Author: lachlanjc

src/templates/docs/font-family/index.html

@@ -187,7 +187,7 @@ <h4 class="f4 mv0 fw6 dib mr4"><%= name %></h4>
             <dd class="db pl0 ml0 f4 f2-ns b"><%= moduleObj.rules.size.average %></dd>
           </dl>
         </div>
-        <kbd>src/_font-families.css</kbd>
+        <kbd>src/_font-family.css</kbd>
       </header>
 <pre class="ph3 ph5-ns">
 <code class="code" style="font-size: .75rem;">