Fix an error for Style/MultilineMethodSignature

[koic]

This PR fixes the following error and the incorrect auto-correct for Style/MultilineMethodSignature when line break after opening parenthesis.

% cat example.rb
class Foo
  def foo(
    arg
)
  end
end

Before

% rubocop -a --only Style/MultilineMethodSignature example.rb
(snip)

Inspecting 1 file
C

Offenses:

example.rb:2:3: C: [Corrected] Style/MultilineMethodSignature: Avoid
multi-line method signatures.
def foo( ...
^^^^^^^^

0 files inspected, 1 offense detected, 1 offense corrected
Infinite loop detected in /private/tmp/example.rb and caused by Style/MultilineMethodSignature
/Users/koic/.rbenv/versions/3.0.0/lib/ruby/gems/3.0.0/gems/rubocop-1.12.0/lib/rubocop/runner.rb:304:in
`check_for_infinite_loop'
/Users/koic/.rbenv/versions/3.0.0/lib/ruby/gems/3.0.0/gems/rubocop-1.12.0/lib/rubocop/runner.rb:287:in
`block in iterate_until_no_changes'
/Users/koic/.rbenv/versions/3.0.0/lib/ruby/gems/3.0.0/gems/rubocop-1.12.0/lib/rubocop/runner.rb:286:in
`loop'
(snip)

% cat example.rb
class Foo
  def foo(
    arg)
  end
end

After

% rubocop -a --only Style/MultilineMethodSignature example.rb
(snip)

class Foo
  def foo(arg)
  end
end

---

Before submitting the PR make sure the following are checked:

• The PR relates to only one subject with a clear title and description in grammatically correct, complete sentences.
• Wrote good commit messages.
• Commit message starts with [Fix #issue-number] (if the related issue exists).
• Feature branch is up-to-date with master (if not - rebase it).
• Squashed related commits together.
• Added tests.
• Ran bundle exec rake default. It executes all tests and runs RuboCop on its own code.
• Added an entry (file) to the changelog folder named {change_type}_{change_description}.md if the new code introduces user-observable changes. See changelog entry format for details.