[ruby/reline] Remove interrupt avoidance

There used to be a process that did not want to be interrupted by
SIGINT, so it was trapped, but that process is no longer there.

https://github.com/ruby/reline/commit/ba7252a5db

lib/reline/ansi.rb

@@ -295,8 +295,6 @@ class Reline::ANSI
 
   def self.prep
     retrieve_keybuffer
-    int_handle = Signal.trap('INT', 'IGNORE')
-    Signal.trap('INT', int_handle)
     nil
   end