[no ci] fix

tests/71_gc.py

@@ -5,7 +5,7 @@ setup_gc_debug_callback(print)
 
 gc.collect()
 def create_garbage():
-    a = [(1,2) for i in range(10000)]
+    a = [(1,2) for i in range(20000)]
     return a
 
 create_garbage()