feat: add priorities to IP address assignment

db/migrate/20210727210551_add_priority_to_ip_addresses.rb

@@ -0,0 +1,6 @@
+class AddPriorityToIPAddresses < ActiveRecord::Migration[5.2]
+  def change
+    add_column :ip_addresses, :priority, :integer
+    IPAddress.where(priority: nil).update_all(priority: 100)
+  end
+end