Update module github.com/stackitcloud/stackit-sdk-go/services/postgresflex to v0.15.0#588

GokceGK merged 1 commit intomainstackitcloud/stackit-sdk-go:mainfrom

renovate/sdkstackitcloud/stackit-sdk-go:renovate/sdkCopy head branch name to clipboard