issue=628: add test for recursive-sc

Author: bennn

typed-racket-test/succeed/issue-628.rkt

@@ -4,15 +4,19 @@
 ;;  successfully **runs**
 
 (module t typed/racket/base
-  (provide f)
+  (provide f g)
 
   (define-type Spec
     (-> (U Spec String)))
 
   (: f (-> Spec))
   (define (f)
+    (λ () "hello"))
+
+  (: g (-> (Rec T (-> (U T String)))))
+  (define (g)
     (λ () "hello")))
 
 (require 't)
 
-(void f)
+(void f g)