STI 父模型和子模型的 ignored_columns 不一致时，缓存可能是错误的

[OuYangJinTing]

class Animal < ApplicationRecord
  self.ignored_columns = [:name]
end

class Dog < Animal
  self.ignored_columns = []
end

def test_sti_ignored_columns_not_match
  animal = Animal.create(name: "Dog", type: "Dog")
  animal.expire_second_level_cache
  Animal.find(animal.id)

  assert_equal "Dog", Animal.fetch_by_uniq_keys(id: animal.id).name
end

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bundle exec rake test result:
Failure:
FetchByUinqKeyTest#test_sti_ignored_columns_not_match [/Code/second_level_cache/test/fetch_by_uniq_key_test.rb:119]:                                                      
Expected: "Dog"                                                                                                                                                           
  Actual: nil