fix fonts in dropdown menu in gradebook

test plan:
  - as a teacher, use gradebook 2.
  - open the gear menu next to the "Showing:All Sections" menu
  - fonts should look consistent.

fixes CNVS-4377

Change-Id: Ie6ca802a738992b60283fdef3440a3e703d13212
Reviewed-on: https://gerrit.instructure.com/18258
Tested-by: Jenkins <jenkins@instructure.com>
Reviewed-by: Simon Williams <simon@instructure.com>
QA-Review: Myller de Araujo <myller@instructure.com>

app/stylesheets/gradebook2.sass

@@ -378,11 +378,21 @@ $gradebook_checkbox_width: 16px
 .gradebook_filter input
   width: 300px
 
+=gradebook_menu_label
+  font-size: 12px
+  font-weight: bold
+  margin-bottom: 0
+  vertical-align: 0px !important
+  position: relative
+  line-height: 1.5
+
 #section-to-show-menu
   width: 200px
   overflow-x: hidden
   overflow-y: auto
   max-height: 550px
+  label
+    +gradebook_menu_label
 
 .submission_type_icon
   display: block
@@ -412,3 +422,8 @@ $gradebook_checkbox_width: 16px
 
 .final-warning
   margin-left: -16px
+
+.gradebook_drop_down
+  label
+    +gradebook_menu_label
+

app/views/gradebook2/show.html.erb

@@ -12,7 +12,7 @@
   <div id="gradebook-toolbar" class="toolbar">
     <button style="display:none;" id="section_to_show">Showing: <span id="section_being_shown">All Sections</span></button>
     <button id="gradebook_settings"><i class="icon-settings"></i></button>
-    <ul style="display: none;">
+    <ul style="display: none;" class="gradebook_drop_down ui-kyle-menu">
       <li><a href="<%= context_url(@context, :context_gradebook_url) %>/history"><%= t('view_grading_history', 'View Grading History') %></a></li>
       <li><a href="<%= context_url(@context, :context_gradebook_url) %>.csv"><%= t('download_scores', 'Download Scores (.csv)') %></a></li>
       <% if @gradebook_is_editable && @context.allows_gradebook_uploads? %>