[Fix #6738] Prevent auto-correct conflict of Style/Next and Style/SafeNavigation

[hoshinotsuyoshi]

Fixes #6738

Solves problem like below:

problem

until x
  if foo
    foo.some_method do
      y
    end
  end
end

auto-corrects badly;

# frozen_string_literal: true

until x
  next unless foofoo&.some_method do
    y
  end
end

( in rubocop.yml, TargetRubyVersion: 2.3 needed(2.3 or higher version). )

new behavior

auto-corrects:

# frozen_string_literal: true

until x
  next unless foo

  foo.some_method do
    y
  end
end

---

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