Move a test file

* test/-ext-/ast/test_ast.rb: This test file
  has not depended C extension since r63534,
  so move to 'test/ruby/'.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@63568 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

test/ruby/test_ast.rb

@@ -111,7 +111,7 @@ class TestAst < Test::Unit::TestCase
     end
   end
 
-  SRCDIR = File.expand_path("../../../..", __FILE__)
+  SRCDIR = File.expand_path("../../..", __FILE__)
 
   Dir.glob("test/**/*.rb", base: SRCDIR).each do |path|
     define_method("test_ranges:#{path}") do