enable some tests

Some tests that rely on a `main` submodule for places
need a `test` submodule, too.

pkgs/racket-test/tests/racket/place-chmsg-gc-acct.rkt

@@ -22,5 +22,5 @@
   (unless (andmap zero? r)
     (error "some place failed")))
 
-
-
+(module+ test
+  (require (submod ".." main)))

pkgs/racket-test/tests/racket/place-cross-phase.rkt

@@ -15,3 +15,6 @@
   (define p (go))
   (printf "waiting\n")
   (place-wait p))
+
+(module+ test
+  (require (submod ".." main)))

pkgs/racket-test/tests/racket/place-kill-unwind.rkt

@@ -24,3 +24,6 @@
     (define p (go))
     (place-channel-get p)
     (place-kill p)))
+
+(module+ test
+  (require (submod ".." main)))

pkgs/racket-test/tests/racket/place-struct-info.rkt

@@ -18,3 +18,6 @@
   (void (place-wait (go)))
   (collect-garbage)
   (void (place-wait (go))))
+
+(module+ test
+  (require (submod ".." main)))

pkgs/racket-test/tests/racket/remote-atomic-write.rkt

@@ -24,3 +24,6 @@
   (unless (equal? 65 (place-channel-get p))
     (error "crash"))
   'ok)
+
+(module+ test
+  (require (submod ".." main)))