Update endpoints model

Author: aws-sdk-swift-automation

codegen/sdk-codegen/sdk-endpoints.json

@@ -17366,6 +17366,7 @@
  "ap-southeast-3" : { },
  "ap-southeast-4" : { },
  "ap-southeast-5" : { },
+ "ap-southeast-6" : { },
  "ap-southeast-7" : { },
  "ca-central-1" : { },
  "ca-west-1" : { },