[ruby/logger] Update lib/logger.rb

https://github.com/ruby/logger/commit/3dc5a8d7a4

Co-authored-by: Peter Zhu <peter@peterzhu.ca>

lib/logger.rb

@@ -245,7 +245,7 @@ require_relative 'logger/errors'
 # With this level, entries with severity Logger::ERROR and higher
 # are written, while those with lower severities are not written:
 #
-#   logger = Logger.new($stdout)
+#   logger = Logger.new($stdout, level: Logger::ERROR)
 #   logger.add(3)
 #   # =? E, [2022-05-11T15:17:20.933362 #20536] ERROR -- : nil
 #   logger.add(2) # Silent.