Re-add create_builtin(sys) test

Author: dr-carlos

Lib/test/test_import/__init__.py

@@ -1258,6 +1258,9 @@ class Spec:
             pass
         spec = Spec()
 
+        spec.name = "sys"
+        self.assertIs(_imp.create_builtin(spec), sys)
+
         spec.name = None
         with self.assertRaisesRegex(TypeError, 'name must be string, not NoneType'):
             _imp.create_builtin(spec)