FIX: do not include username in assign push notification

config/locales/server.en.yml

@@ -18,7 +18,7 @@ en:
     already_claimed: "That topic has already been claimed."
     flag_assigned: "Sorry, that flag's topic is assigned to another user"
     flag_unclaimed: "You must claim that topic before acting on the flag"
-    topic_assigned_excerpt: "@%{username} assigned you the topic '%{title}'"
+    topic_assigned_excerpt: "assigned you the topic '%{title}'"
   assign_mailer:
     title: "Assign Mailer"
     subject_template: "[%{email_prefix}] %{assignee_name} assigned you to '%{topic_title}'!"

lib/topic_assigner.rb

@@ -215,8 +215,9 @@ SQL
       alerter.create_notification_alert(
         user: assign_to,
         post: first_post,
+        username: @assigned_by.username,
         notification_type: Notification.types[:custom],
-        excerpt: I18n.t("discourse_assign.topic_assigned_excerpt", title: @topic.title, username: @assigned_by.username)
+        excerpt: I18n.t("discourse_assign.topic_assigned_excerpt", title: @topic.title)
       )
     end
 

spec/lib/topic_assigner_spec.rb

@@ -38,7 +38,7 @@ RSpec.describe TopicAssigner do
       end
 
       expect(messages.length).to eq(1)
-      expect(messages.first.data[:excerpt]).to eq("@#{moderator2.username} assigned you the topic '#{topic.title}'")
+      expect(messages.first.data[:excerpt]).to eq("assigned you the topic '#{topic.title}'")
 
       expect(TopicQuery.new(
         moderator, assigned: moderator.username