chore: remove old executor spec workaround

Author: devnote-dev

src/cling.cr

@@ -11,11 +11,3 @@ require "./cling/value"
 module Cling
   VERSION = "3.0.0"
 end
-
-# TODO: move this to cling/spec
-{% if @top_level.has_constant?("Spec") %}
-  module Cling::Executor
-    private def self.handle_exit(ex : Cling::ExitProgram) : Nil
-    end
-  end
-{% end %}