docs: merge manual use-case for org-three-way with sns (#139)

Author: iru

use-cases/README.md

@@ -11,8 +11,7 @@ Check [current use-case list](https://github.com/sysdiglabs/terraform-aws-secure
 Secure for cloud is served through Terraform for [AWS](https://github.com/sysdiglabs/terraform-aws-secure-for-cloud) 
 [GCP](https://github.com/sysdiglabs/terraform-google-secure-for-cloud) and [Azure](https://github.com/sysdiglabs/terraform-azurerm-secure-for-cloud) clouds, 
 and for AWS in [Cloudformation](https://github.com/sysdiglabs/aws-templates-secure-for-cloud) too.
-
-If not Terraform nor Cloudformation suits, take a look at the `manual-*` prefixed use-cases.
+<br/>If not Terraform nor Cloudformation suits, take a look at the `manual-*` prefixed use-cases.
 
 
 ## Use-Case summary