def check_files(files)
      files.each { |file| check_file(file) if file.is_a? String }
    end
def check_files(files)
      files.each { |file| check_file(file) if file.is_a? String }
    end
Checks if in the files `NSLog` or `print` are used.
 @param files [Array<String>] List of interested / modified files to check.

 @return [Void]