Remove unused trackers form

This file was probably generated automatically and we forgot to remove
it. We never use it; the edit action includes its own form.

app/views/admin/trackers/_form.html.erb

@@ -1,32 +0,0 @@
-<%= form_for(tracker) do |f| %>
-  <% if tracker.errors.any? %>
-    <div id="error_explanation">
-      <h2><%= pluralize(tracker.errors.count, "error") %> prohibited this tracker from being saved:</h2>
-
-      <ul>
-      <% tracker.errors.full_messages.each do |message| %>
-        <li><%= message %></li>
-      <% end %>
-      </ul>
-    </div>
-  <% end %>
-
-  <div class="field">
-    <%= f.label :user_id %>
-    <%= f.text_field :user_id %>
-  </div>
-
-  <div class="field">
-    <%= f.label :description %>
-    <%= f.text_field :description %>
-  </div>
-
-  <div class="field">
-    <%= f.label :budget_investment_count %>
-    <%= f.number_field :budget_investment_count %>
-  </div>
-
-  <div class="actions">
-    <%= f.submit %>
-  </div>
-<% end %>