server: Add lease checkpointing fix information to CHANGELOG

Author: serathius

CHANGELOG-3.5.md

@@ -14,6 +14,8 @@ See [code changes](https://github.com/etcd-io/etcd/compare/v3.5.1...v3.5.2) and
 
 ### etcd server
 - Fix [exclude the same alarm type activated by multiple peers](https://github.com/etcd-io/etcd/pull/13476).
+- Add [`etcd --experimental-enable-lease-checkpoint-persist`](https://github.com/etcd-io/etcd/pull/13508) flag to enable checkpoint persisting.
+- Fix [Lease checkpoints don't prevent to reset ttl on leader change](https://github.com/etcd-io/etcd/pull/13508), requires enabling checkpoint persisting.
 
 <hr>
 

CHANGELOG-3.6.md

@@ -33,9 +33,11 @@ See [code changes](https://github.com/etcd-io/etcd/compare/v3.5.0...v3.6.0).
 
 - Add [`etcd --log-format`](https://github.com/etcd-io/etcd/pull/13339) flag to support log format.
 - Add [`etcd --experimental-max-learners`](https://github.com/etcd-io/etcd/pull/13377) flag to allow configuration of learner max membership.
+- Add [`etcd --experimental-enable-lease-checkpoint-persist`](https://github.com/etcd-io/etcd/pull/13508) flag to handle upgrade from v3.5.2 clusters with this feature enabled.
 - Fix [non mutating requests pass through quotaKVServer when NOSPACE](https://github.com/etcd-io/etcd/pull/13435)
 - Fix [exclude the same alarm type activated by multiple peers](https://github.com/etcd-io/etcd/pull/13467).
 - Fix [Provide a better liveness probe for when etcd runs as a Kubernetes pod](https://github.com/etcd-io/etcd/pull/13399)
+- Fix [Lease checkpoints don't prevent to reset ttl on leader change](https://github.com/etcd-io/etcd/pull/13508).
 
 ### tools/benchmark