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• I've Updated SwiftLint to the latest version.
• I've searched for existing GitHub issues.

Bug Description

Using file_header with a configured pattern triggers violation. This appeared after upgrading to 0.60.0 (it worked fine with 0.59.1 and previous versions).

// This triggers a violation:

//
//  Test.swift
//  Dummy App
//
//  Created by Xavi R. Pinteño on 3.9.2025.
//  Copyright © 2025 Dummy Corporation. All rights reserved.
//

enum Test {
}

Mention the command or other SwiftLint integration method that caused the issue. Include stack traces or command output.

$ swiftlint lint Test.swift

Environment

• SwiftLint version 0.60.0
• Xcode version 16.4. Build version 16F6
• Installation method used: Homebrew
• Configuration file:

opt_in_rules:
  - file_header

file_header:
  required_pattern: |
                    \/\/
                    \/\/  SWIFTLINT_CURRENT_FILENAME
                    \/\/  .*?
                    \/\/
                    \/\/  Created by .*? on \d{1,2}[\.\/]\d{1,2}[\.\/]\d{2,4}\.
                    \/\/  Copyright © \d{4} Dummy Corporation\. All rights reserved\.
                    \/\/

• Nested configurations: No