Remove dead code in order

These aren't used anywhere

app/models/spree/order.rb

@@ -135,18 +135,6 @@ module Spree
 
     scope :finalized, -> { where(state: FINALIZED_STATES) }
 
-    def self.by_number(number)
-      where(number: number)
-    end
-
-    def self.between(start_date, end_date)
-      where(created_at: start_date..end_date)
-    end
-
-    def self.by_customer(customer)
-      joins(:user).where("#{Spree.user_class.table_name}.email" => customer)
-    end
-
     def self.by_state(state)
       where(state: state)
     end