Fix TimerTask example output

bensheldon · bensheldon · commit 841eed2fb721 · 2023-07-05T09:04:00.000-07:00
diff --git a/lib/concurrent-ruby/concurrent/timer_task.rb b/lib/concurrent-ruby/concurrent/timer_task.rb
@@ -101,6 +101,7 @@ module Concurrent
   #   #=> Boom! Boom!
   #   #=> Boom! Boom! Boom!
   #   #=> Boom! Boom! Boom! Boom!
+  #   #=> Boom! Boom! Boom! Boom! Boom!
   #   #=> Stopping...
   #
   # @example Observation
