Topic management: add link to topic detail page

Changelog: added

app/views/admin/topics/_topic.html.haml

@@ -6,7 +6,7 @@
 
   .gl-min-w-0.gl-flex-grow-1
     .title
-      = topic.name
+      = link_to topic.name, topic_explore_projects_path(topic_name: topic.name)
 
   .stats.gl-text-gray-500.gl-flex-shrink-0.gl-display-none.gl-sm-display-flex
     %span.gl-ml-5.has-tooltip{ title: n_('%d project', '%d projects', topic.total_projects_count) % topic.total_projects_count }