[Fix #9773] Fix Style/EmptyLiteral to not register offenses for String.new when Style/FrozenStringLiteral is enabled

[dvandersluis]

Style/EmptyLiteral replaces String.new with '', unless the file has a frozen-string-literal: true magic comment. However, if Style/FrozenStringLiteral is also enabled, this will cause broken code, because the magic comment will be added afterwards.

This change makes string behaviour the same if Style/FrozenStringLiteral is enabled as if the magic comment is found. However, if Style/FrozenStringLiteral is enabled but there is a frozen-string-literal: false magic comment, Style/EmptyLiteral will continue to replace the literal.

Fixes #9773.

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[adfoster-r7]

Ran this against our codebase and it worked great - thanks for looking into this! 👍

[koic]

Cool👍 This solution approach to the issue seems to make sense!