Fix an incorrect auto-correct for Style/StructInheritance

[koic]

This PR fixes the following incorrect auto-correct for Style/StructInheritance incorrect auto-correct for Style/StructInheritance when there is a comment before class declaration.

% cat example.rb
# comment
class Foo < Struct.new(:foo)
end

% bundle exec rubocop --only Style/StructInheritance -a
(snip)

Offenses:

example.rb:2:13: C: [Corrected] Style/StructInheritance: Don't extend an
instance initialized by Struct.new. Use a block to customize the struct.
class Foo < Struct.new(:foo)
            ^^^^^^^^^^^^^^^^

1 file inspected, 1 offense detected, 1 offense corrected

% cat example.rb
# commentFoo = Struct.new(:foo) do
end

This issue has been reported on rubocop-jp. (Japanese)
rubocop/rubocop-jp#61

---

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