docs: be more explicit about the change in the CHANGELOG

Author: dervoeti

crates/stackable-operator/CHANGELOG.md

@@ -20,7 +20,7 @@ All notable changes to this project will be documented in this file.
 
 - BREAKING: Bump Rust dependencies to enable Kubernetes 1.32 (via `kube` 0.98.0 and `k8s-openapi`
   0.23.0) ([#867]).
-- BREAKING: Append a dot to the default cluster domain and allow a trailing dot in `DomainName` ([#939]).
+- BREAKING: Append a dot to the default cluster domain to make it a FQDN and allow FQDNs when validating a `DomainName` ([#939]).
 
 [#939]: https://github.com/stackabletech/operator-rs/pull/939