title: Unable to upgrade elastic search from 5 to 6
body: <p>I am trying to run the upgrade assistant in order to upgrade ElasticSearch from 5 to 6, however I am hitting the following error:</p>
  
  <pre><code>Deprecated script security settings changes
  This issue must be resolved to upgrade. Read Documentation
  Details: [node[instance-0000000093] used these script-security settings:[script.inline, script.stored, script.file, script.engine.painless.stored, script.engine.painless.file, script.engine.expression.stored, script.engine.expression.file, script.engine.mustache.inline, script.engine.mustache.stored, script.engine.mustache.file]]
  </code></pre>
  
  <p>I have looked over the settings and our Kibana config and cannot find any references to any scrips being used.</p>
  
  <p>Has anyone else run into a similar issue and how did you solve it?</p>
  
  <p>Thanks.</p>