Update docs

docs/dev/04_materialize_templates.rst

@@ -56,13 +56,13 @@ Furthermore, you can use tabs with integrated icons that are higher, but more co
         <ul class="tabs tabs-transparent tabs-icons tabs-fixed-width">
             <li class="tab">
                 <a href="#test1">
-                    <i class="material-icons">speaker_notes</i>
+	            <i class="material-icons iconify" data-icon="mdi:speaker_notes"></i>
                     Test 1
                 </a>
             </li>
             <li class="tab">
                 <a href="#test2">
-                    <i class="material-icons">people</i>
+                    <i class="material-icons iconify" data-icon="mdi:people"></i>
                     Test 2
                 </a>
             </li>