burs/show: remove BUR update count estimate.

Remove the post update count estimate from BUR show pages. This was
complex, slow, and usually inaccurate since it assumed that requests in
a BUR had no overlap with each other, which usually wasn't the case.

app/views/bulk_update_requests/show.html.erb

@@ -9,7 +9,6 @@
       <li><strong>Creator</strong> <%= link_to_user @bulk_update_request.user %></li>
       <li><strong>Date</strong> <%= @bulk_update_request.created_at %></li>
       <li><strong>Status</strong>: <%= @bulk_update_request.status %></li>
-      <li><strong title="How many posts will be affected">Estimate</strong>: <%= @bulk_update_request.estimate_update_count %></li>
     </ul>
 
     <div style="margin: 1em 0;">