Remove call to class name in scope

Co-authored-by: Juan Vásquez <juan@ombulabs.com>

Author: mateusdeap

app/models/puzzle.rb

@@ -3,5 +3,5 @@ class Puzzle < ApplicationRecord
   enum :state, { approved: 0, rejected: 1, pending: 2, archived: 3 }
   has_many :answers
 
-  scope :archived, -> { Puzzle.where(state: :archived).order(sent_at: :desc) }
+  scope :archived, -> { where(state: :archived).order(sent_at: :desc) }
 end