update 3.6 CHANGELOG
@@ -45,6 +45,7 @@ See [code changes](https://github.com/etcd-io/etcd/compare/v3.5.0...v3.6.0).
- Fix [A client can panic etcd by passing invalid utf-8 in the client-api-version header](https://github.com/etcd-io/etcd/pull/13560)
- Fix [etcd gateway doesn't format the endpoint of IPv6 address correctly](https://github.com/etcd-io/etcd/pull/13551)
- Fix [A client can cause a nil dereference in etcd by passing an invalid SortTarget](https://github.com/etcd-io/etcd/pull/13555)
+- Fix [Grant lease with negative ID can possibly cause db out of sync](https://github.com/etcd-io/etcd/pull/13676)
### tools/benchmark
