Issue #3267052 by quietone, daffie: Move aggregator help topics to aggregator module

(cherry picked from commit 835a4fe196)

core/modules/help_topics/help_topics/core.content_structure.html.twig

@@ -36,7 +36,7 @@ top_level: true
 <h2>{% trans %}Managing content structure overview{% endtrans %}</h2>
 <p>{% trans %}Besides the field modules listed in the previous section, there are additional core modules that you can use to manage your content structure:{% endtrans %}</p>
 <ul>
-  <li>{% trans %}The core Node, Comment, Custom Block, Custom Menu Links, User, File, Image, Media, Taxonomy, Contact, and Aggregator modules all provide content entity types.{% endtrans %}</li>
+  <li>{% trans %}The core Node, Comment, Custom Block, Custom Menu Links, User, File, Image, Media, Taxonomy, and Contact modules all provide content entity types.{% endtrans %}</li>
   <li>{% trans %}The core Field UI module provides a user interface for managing fields and their display on entities.{% endtrans %}</li>
   <li>{% trans %}The core Layout Builder module provides a more flexible user interface for configuring the display of entities.{% endtrans %}</li>
   <li>{% trans %}The core Filter, RDF, Responsive Image, and Path modules provide settings and display options for entities and fields.{% endtrans %}</li>