Use full group name in GFM group reference title

changelogs/unreleased/dm-group-reference-full-name.yml

+---
+title: Use full group name in GFM group reference title
+merge_request:
+author:

lib/banzai/filter/user_reference_filter.rb

@@ -133,7 +133,7 @@ module Banzai
         data = data_attribute(group: namespace.id)
         content = link_content || Group.reference_prefix + group
 
-        link_tag(url, data, content, namespace.name)
+        link_tag(url, data, content, namespace.full_name)
       end
 
       def link_to_user(user, namespace, link_content: nil)

spec/lib/banzai/filter/user_reference_filter_spec.rb

@@ -123,6 +123,12 @@ describe Banzai::Filter::UserReferenceFilter, lib: true do
 
       expect(doc.css('a').first.attr('href')).to eq urls.group_url(group)
     end
+
+    it 'has the full group name as a title' do
+      doc = reference_filter("Hey #{reference}")
+
+      expect(doc.css('a').first.attr('title')).to eq group.full_name
+    end
   end
 
   it 'links with adjacent text' do