message: docs: fixed that class attribute is not closed
  PR Close
diff: @@ -569,7 +569,7 @@ which can only be reached by querying for them via the property decorated with
  {@a no-unidirectional-flow-worries}
  -<div class="alert is-helpful>
  +<div class="alert is-helpful">
  <header>No need to wait for content updates</header>
  