title: How to handle `MongoException`?
body: <p>I don't know, how to detect and handle <code>MongoException</code> in case of <code>MongoDB disconnect</code></p>
  
  <pre><code>  val pingCmd: Publisher[bson.Document] = mongoCollFactory.db.runCommand(BsonDocument.parse("""{"ping": 1}"""))
  </code></pre>
  
  <p>detect <code>MongoException</code> which does not connect to the database and then returns <code>MongoException</code>
  Ex. <code>when pingCmd is success -&gt; HealthCheck.OK
  then pingCmd failed -&gt; HealthCheck.Failed</code></p>