Update bundled_gems

Author: hsbt

gems/bundled_gems

@@ -41,7 +41,7 @@ benchmark           0.4.0   https://github.com/ruby/benchmark
 logger              1.7.0   https://github.com/ruby/logger
 rdoc                6.13.1  https://github.com/ruby/rdoc
 win32ole            1.9.1   https://github.com/ruby/win32ole
-irb                 1.15.1  https://github.com/ruby/irb 6bb53630c3398b2042fb99d5232c68399491d338
+irb                 1.15.2  https://github.com/ruby/irb
 reline              0.6.0   https://github.com/ruby/reline defcd36c0b6e6648333d4b9ab5923eb4e543615e
 readline            0.0.4   https://github.com/ruby/readline
 fiddle              1.1.6   https://github.com/ruby/fiddle