doc: replace URL action example with form The example to provide a link to take or resolve an item was broken. Roundup has required a POST not GET for changes to the database for a while. This example was never fixed. Replaced a link using GET with a POSTed form. This changes the activating element from a link to a button. The button could be restyled as a link using CSS I think. The original example was also not canonical. It used :action rather than the canonical @action.

<!-- dollarId: issue.item,v 1.4 2001/08/03 01:19:43 richard Exp dollar-->
<tal:block metal:use-macro="templates/page/macros/icing">
  <title metal:fill-slot="head_title">
  Item Not Found
  </title>
  <tal:block metal:fill-slot="body_title">
  Item Not Found
  </tal:block>

<td class="content" metal:fill-slot="content">
    There is no <span tal:content="context/_classname" /> with id
    <span tal:content="context/id"/>
</td>
</tal:block>