Use @repository

app/controllers/projects/avatars_controller.rb

@@ -2,11 +2,10 @@ class Projects::AvatarsController < Projects::ApplicationController
   before_action :project
 
   def show
-    repository = @project.repository
-    @blob = repository.blob_at_branch('master', @project.avatar_in_git)
+    @blob = @repository.blob_at_branch('master', @project.avatar_in_git)
     if @blob
       headers['X-Content-Type-Options'] = 'nosniff'
-      headers.store(*Gitlab::Workhorse.send_git_blob(repository, @blob))
+      headers.store(*Gitlab::Workhorse.send_git_blob(@repository, @blob))
       headers['Content-Disposition'] = 'inline'
       headers['Content-Type'] = @blob.content_type
       head :ok # 'render nothing: true' messes up the Content-Type