mod_http_oauth2: Remove broken in-CSS templating Because util.interpolation with a "%b{}" pattern only matches the outer brackets, so variables inside them would not work unless the pattern is changed (also considered).

<tr>
  <th>What is {x} {op} {y}?</th><td>
    <input name="captcha_challenge" type="hidden" value="{challenge}">
    <input name="captcha_reply" pattern="[0-9]+" required type="number">
  </td></tr>