This rule was added in rubocop-rails 2.33.
At first, I wasn't very fond of this rule. It made the code less
readable even if it improved performace in some cases.
Then I realized that in the `Admin::MachineLearning::SettingComponent`
we were using `find_by` when we should be using `find_by!` instead, and
we detected that thanks to this rule.
So, only for that reason, I'm adding this rule, but I'm fine if we
remove it.