private_over_fileprivate produces a false positive when using actor

[jbttn]

New Issue Checklist

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

Describe the bug

private_over_fileprivate produces a false positive when using actor.

Environment

• SwiftLint version (run swiftlint version to be sure)? 0.53.0
• Installation method used (Homebrew, CocoaPods, building from source, etc)? Homebrew
• Paste your configuration file:

disabled_rules:
  - todo

file_length:
  ignore_comment_only_lines: true
function_body_length: 75
identifier_name:
  excluded:
    - i
    - j
    - id
    - db
line_length:
  ignores_comments: true
type_name:
  excluded:
    - ID
    - L

Are you using nested configurations?

No

Which Xcode version are you using (check xcodebuild -version)?

Xcode 15.3
Build version 15E204a

Do you have a sample that shows the issue? Run echo "[string here]" | swiftlint lint --no-cache --use-stdin --enable-all-rules
to quickly test if your example is really demonstrating the issue. If your example is more
complex, you can use swiftlint lint --path [file here] --no-cache --enable-all-rules.

import SwiftUI

extension EnvironmentValues {
    var foo: Foo { .shared }
}

actor Foo {
  fileprivate static let shared = Foo() // Triggers the warning
}

//class Foo {
//  fileprivate static let shared = Foo() // Does not trigger the warning
//}