title: vue-language-server : Elements in iteration expect to have 'v-bind:key' directives
body: <p>Vue.js 2.5 / Visual Studio Code editor</p>
  <p>I am getting this es-lint warning, how can I get rid of it ?</p>
  <pre class="lang-html prettyprint-override"><code>&lt;template :slot=&quot;slotName&quot; slot-scope=&quot;props&quot; v-for=&quot;slotName in  $scopedSlots?Object.keys($scopedSlots):null&quot;&gt;
      &lt;slot :name=&quot;slotName&quot; :row-data=&quot;props.rowData&quot; :row-index=&quot;props.rowIndex&quot; :row-field=&quot;props.rowField&quot;&gt;&lt;/slot&gt;
  &lt;/template&gt;
  </code></pre>
  <p>I tried to add an index, but it does not solve this issue</p>
  <pre class="lang-html prettyprint-override"><code>&lt;template :slot=&quot;slotName&quot; slot-scope=&quot;props&quot; v-for=&quot;(slotName, index) in  $scopedSlots?Object.keys($scopedSlots):null&quot; :key=&quot;index&quot;&gt;
      &lt;slot :name=&quot;slotName&quot; :row-data=&quot;props.rowData&quot; :row-index=&quot;props.rowIndex&quot; :row-field=&quot;props.rowField&quot;&gt;&lt;/slot&gt;
  &lt;/template&gt;
  </code></pre>