fix ref link in cognito-rds-s3 guide (#430)

**Description of your changes:**
- fix ref link in cognito-rds-s3 guide

**Testing:**
- manual

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under the terms of the Apache 2.0 license.

website/content/en/docs/deployment/cognito-rds-s3/guide.md

@@ -21,7 +21,7 @@ Refer to the [general prerequisites guide]({{< ref "/docs/deployment/prerequisit
 
 ## Configure Custom Domain and Cognito
 
-1. Follow the Section 2.0 of [Cognito setup guide]({{< ref "/docs/deployment/cognito/manifest/guide-automated/#20-create-required-resources" >}}) in order to:
+1. Follow the Section 2.0 of [Cognito setup guide]({{< ref "/docs/deployment/cognito/manifest/guide-automated.md#20-create-required-resources" >}}) in order to:
     1. Create a custom domain
     1. Create TLS certificates for the domain
     1. Create a Cognito Userpool