Fix article table UI

Author: adrien1018

TODOLIST.md

@@ -3,7 +3,7 @@
     - Lower priority
     - Separate contest and non-contest submissions
 - [ ] Virtual judge
-- [ ] Batch upload testdata
+- [x] Batch upload testdata
 - [ ] Revisit all JSON endpoints
 - [ ] Revisit all ActiveAdmin pages & Upgrade to ActiveAdmin 3
 ---

app/views/articles/_table.html.erb

@@ -4,7 +4,9 @@
       <th class="col-md-5"><%= pin_glyph %> Title</th>
       <th class="col-md-3">Time</th>
       <th class="col-md-3">Author</th>
-      <th class="col-md-1"></th>
+      <% if current_user&.admin? %>
+        <th class="col-md-1"></th>
+      <% end %>
     </tr>
   </thead>
   <tbody>