Autocorrect for "redundant_void_return" corrupts file when preprocessor macros are present

[jszumski]

New Issue Checklist

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

This is almost identical to #2099.

Bug Report

Complete output when running SwiftLint, including the stack trace and command used

$ swiftlint autocorrect --path Foo.swift
Correcting Swift files at path Foo.swift
Correcting 'Foo.swift' (1/1)
Foo.swift:3:15 Corrected Redundant Void Return
Foo.swift:3:15 Corrected Redundant Void Return
Done correcting 1 files!

Environment

• SwiftLint version (run swiftlint version to be sure)? 0.25.0
• Installation method used (Homebrew, CocoaPods, building from source, etc)? Homebrew
• Paste your configuration file:

whitelist_rules:
  - redundant_void_return

• Are you using nested configurations? If so, paste their relative paths and respective contents. no
• Which Xcode version are you using (check xcode-select -p)? 9.2

Steps to Reproduce

Source File

protocol Foo {
    #if true
    func foo() -> Void
    #endif
}

Run autocorrect

$ swiftlint autocorrect --path Foo.swift
Correcting Swift files at path Foo.swift
Correcting 'Foo.swift' (1/1)
Foo.swift:3:15 Corrected Redundant Void Return
Foo.swift:3:15 Corrected Redundant Void Return
Done correcting 1 files!

Corrected File

The duplicate correction ends up truncating remaining parts of the file.

protocol Foo {
    #if true
    func foo()dif
}