[Fix #13374] Return exit code 0 with --display-only-correctable and --display-only-safe-correctable when no offenses are displayed

[dvandersluis]

When --display-only-correctable or --display-only-safe-correctable is specified, and therefore no offenses are included that'd otherwise be shown, return exit code 0 instead of 1.

Fixes #13374.

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[koic]

Thanks!

[vasil-nesterov]

Thank you Daniel!