message: docs: change wrong alert to callout
  change the alert present in the lifecycicle-hook docs to a callout so
  that its header can be properly rendered (since alters don't support have headers)
  PR Close
diff: @@ -320,7 +320,7 @@ The following *AfterContent* hooks take action based on changing values in a *co
  <a id="no-unidirectional-flow-worries"></a>
  -<div class="alert is-helpful">
  +<div class="callout is-helpful">
  <header>No need to wait for content updates</header>
  