Update wafv2_rule_group.html.markdown

Author: ewbankkit

website/docs/r/wafv2_rule_group.html.markdown

@@ -379,7 +379,7 @@ The `captcha` block supports the following arguments:
 
 The `challenge` block supports the following arguments:
 
-* `custom_request_handling` - (Optional) Defines custom handling for the web request. See [Custom Request Handling](#custom_request_handling) below for details.
+* `custom_request_handling` - (Optional) Defines custom handling for the web request. See [Custom Request Handling](#custom-request-handling) below for details.
 
 ### Count