fix: Fixed tests and stdlib debug code

src/std/time.les

@@ -5,13 +5,4 @@ export def sleep(x: float)
     usleep(y as int)
 
 export def sleep(x: int)
-    usleep(x * 1000000)
-
-export class Animal
-    var x: int
-
-    def new()
-        self.x = 101
-
-    def getX() -> int
-        return self.x
+    usleep(x * 1000000)

tests/lesma/class.les

@@ -1,7 +1,7 @@
 #ret=101
 def extern exit(x: int)
 
-class Animal
+export class Animal
     var x: int
 
     def new()

tests/lesma/import_std_into_scope.les

@@ -1,7 +1,8 @@
 #ret=101
 from time import sleep as sleep_test
 from "class.les" import Animal
+def extern exit(x: int)
 
 let y = Animal()
 sleep_test(0.1)
-return y.getX()
+exit(y.getX())