misc/lnav: Fix delimiting of timestamp in pattern The string with the timestamp format in core.loggingmanager does end with a space, so having the exact same string here is nice, but the pattern did not reflect this.

<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>