Add search-with-autocomplete JS dependency

government-frontend doesn't call search-with-autocomplete directly,
but instead calls it via the super navigation header in the layout for
public that it injests via static.

app/assets/javascripts/application.js

@@ -7,6 +7,7 @@
 //= require govuk_publishing_components/components/metadata
 //= require govuk_publishing_components/components/print-link
 //= require govuk_publishing_components/components/radio
+//= require govuk_publishing_components/components/search-with-autocomplete
 //= require govuk_publishing_components/components/single-page-notification-button
 //= require govuk_publishing_components/components/step-by-step-nav