Command line option combination --display-only-fail-level-offenses and -A seems not validated correctly

[nobuyo]

I think I found a code that references an incorrect key for options.

https://github.com/rubocop/rubocop/blob/master/lib/rubocop/options.rb#L381-L383

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Expected behavior

rubocop --display-only-fail-level-offenses -A should return an error and exit.

Actual behavior

rubocop --display-only-fail-level-offenses -A runs without any errors.

Steps to reproduce the problem

Execute the aforementioned command.

RuboCop version

$ [bundle exec] rubocop -V
1.27.0 (using Parser 3.1.1.0, rubocop-ast 1.17.0, running on ruby 2.7.1 x86_64-darwin19)
  - rubocop-performance 1.13.3
  - rubocop-rake 0.6.0
  - rubocop-rspec 2.9.0

[nobuyo]

@bbatsov How should I fix this?
This may be a kind of breaking change for users using the options if fixed🤔