title: MaxLength for bootstrap-vue input number Vue.js
body: <p>I try to implement a <code>maxLength</code> for an input from <code>bootstrap-vue</code>, but from what I read from their documentation they don't support max. If I remove <code>type="number"</code>, it works , but is not a number anymore.</p>
  
  <pre><code>    &lt;b-form-input
          size="sm"
          v-model="register_volume_first"
          type="number"
          maxlength=4
          placeholder="1902"
      &gt;&lt;/b-form-input&gt;
  </code></pre>