fixed link to debounce filter

Author: crswll

source/guide/forms.md

@@ -328,4 +328,4 @@ new Vue({
 </script>
 {% endraw %}
 
-Note that the `debounce` param does not debounce the user's input events: it debounces the "write" operation to the underlying data. Therefore you should use `vm.$watch()` to react to data changes when using `debounce`. For debouncing real DOM events you should use the [debounce filter](/api/filters.html#debounce).
+Note that the `debounce` param does not debounce the user's input events: it debounces the "write" operation to the underlying data. Therefore you should use `vm.$watch()` to react to data changes when using `debounce`. For debouncing real DOM events you should use the [debounce filter](/api/#debounce).