Correct the link in the logo (#5372)

Author: annagav

ui/templates/header.html

@@ -1,7 +1,7 @@
   <nav class="navbar" role="navigation">
       <div class="navbar-header">
         <div class="pull-left">
-          <a class="brand-logo" href="http://www.micromasters.mit.edu" rel="noopener noreferrer"></a>
+          <a class="brand-logo" href="{{ request.build_absolute_uri }}" rel="noopener noreferrer"></a>
         </div>
         <div class="pull-right" style="padding-top:4px">
           {% if authenticated %}