Fix an incorrect auto-correct for Style/EvalWithLocation

[koic]

Fixes standardrb/standard#275.

This PR fixes the following incorrect auto-correct for Style/EvalWithLocation when using #instance_eval with a string argument in parentheses.

% cat example.rb
instance_eval('@foo = foo')

% rubocop -A --only Style/EvalWithLocation
(snip)

Inspecting 1 file
C

Offenses:

example.rb:1:1: C: [Corrected] Style/EvalWithLocation: Pass __FILE__ and
__LINE__ to instance_eval.
instance_eval('@foo = foo')
^^^^^^^^^^^^^^^^^^^^^^^^^^^

1 file inspected, 1 offense detected, 1 offense corrected

Before

% cat example.rb
instance_eval('@foo = foo'), __FILE__, __LINE__

% ruby -c example.rb
example.rb:1: syntax error, unexpected ',', expecting end-of-input
instance_eval('@foo = foo'), __FILE__, __LINE__

After

% cat example.rb
instance_eval('@foo = foo', __FILE__, __LINE__)

% ruby -c example.rb
Syntax OK

---

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• 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).
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• 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.