Merge pull request #8939 from ctiller/fixit24

Fix use-after-free in resource quota

src/core/lib/iomgr/resource_quota.c

@@ -231,6 +231,7 @@ static void rulist_remove(grpc_resource_user *resource_user, grpc_rulist list) {
       resource_user->links[list].prev;
   resource_user->links[list].prev->links[list].next =
       resource_user->links[list].next;
+  resource_user->links[list].next = resource_user->links[list].prev = NULL;
 }
 
 /*******************************************************************************