[ruby/irb] Use a real screen size for pp by default

https://github.com/ruby/irb/commit/9b9300dec2

lib/irb/color_printer.rb

@@ -4,7 +4,7 @@ require 'irb/color'
 
 module IRB
   class ColorPrinter < ::PP
-    def self.pp(obj, out = $>, width = 79)
+    def self.pp(obj, out = $>, width = Reline.get_screen_size.last)
       q = ColorPrinter.new(out, width)
       q.guard_inspect_key {q.pp obj}
       q.flush