Update CHANGELOG

Signed-off-by: Kemal Akkoyun <kakkoyun@gmail.com>

CHANGELOG.md

@@ -22,6 +22,7 @@ We use *breaking* word for marking changes that are not backward compatible (rel
 - [#1970](https://github.com/thanos-io/thanos/issues/1970) *breaking* Receive: Use gRPC for forwarding requests between peers. Note that existing values for the `--receive.local-endpoint` flag and the endpoints in the hashring configuration file must now specify the receive gRPC port and must be updated to be a simple `host:port` combination, e.g. `127.0.0.1:10901`, rather than a full HTTP URL, e.g. `http://127.0.0.1:10902/api/v1/receive`.
 - [#1939](https://github.com/thanos-io/thanos/pull/1939) Ruler: Add TLS and authentication support for query endpoints with the `--query.config` and `--query.config-file` CLI flags. See [documentation](docs/components/rule.md/#configuration) for further information.
 - [#1982](https://github.com/thanos-io/thanos/pull/1982) Ruler: Add support for Alertmanager v2 API endpoints.
+- [#2008](https://github.com/thanos-io/thanos/pull/2008) Querier, Receiver, Sidecar, Store: Add gRPC [health check](https://github.com/grpc/grpc/blob/master/doc/health-checking.md) endpoints.
 
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