Remove tests which can not be compiled on CRuby.

test/t/codegen.rb

@@ -14,24 +14,6 @@ assert('empty condition in ternary expression parses correctly') do
   assert_equal(() ? 1 : 2, 2)
 end
 
-assert('codegen absorbs arguments to redo and retry if they are the argument of a call') do
-  assert_nothing_raised do
-    a=*"1", case nil
-    when 1
-      redo |
-      1
-    end
-  end
-
-  assert_nothing_raised do
-    a=*"1", case nil
-    when 1
-      retry |
-      1
-    end
-  end
-end
-
 assert('method call with exactly 127 arguments') do
   def args_to_ary(*args)
     args