Fix the forward test

tests/js/tasync.nim

@@ -1,7 +1,6 @@
 discard """
   disabled: true
   output: '''
-0
 x
 e
 '''
@@ -11,7 +10,7 @@ import asyncjs
 
 # demonstrate forward definition
 # for js
-proc y(e: int): Future[string]
+proc y(e: int): Future[string] {.async.}
 
 proc e: int {.discardable.} =
   echo "e"
@@ -23,8 +22,10 @@ proc x(e: int): Future[void] {.async.} =
   e()
 
 proc y(e: int): Future[string] {.async.} =
-  echo 0
-  return "x"
+  if e > 0:
+    return await y(0)
+  else:
+    return "x"
 
 
 discard x(2)