update changelog

Signed-off-by: Ben Ye <[email protected]>

CHANGELOG.md

@@ -12,8 +12,8 @@ We use *breaking :warning:* to mark changes that are not backward compatible (re
 ## Unreleased
 
 - [#3261](https://github.com/thanos-io/thanos/pull/3261) Thanos Store: Use segment files specified in meta.json file, if present. If not present, Store does the LIST operation as before.
-- [#3276](https://github.com/thanos-io/thanos/pull/3276) Query Frontend: Support query splitting and retry for labels and series requests.
-- [#3315](https://github.com/thanos-io/thanos/pull/3315) Query Frontend: Support results caching for labels and series requests.
+- [#3276](https://github.com/thanos-io/thanos/pull/3276) Query Frontend: Support query splitting and retry for label names, label values and series requests.
+- [#3315](https://github.com/thanos-io/thanos/pull/3315) Query Frontend: Support results caching for label names, label values and series requests.
 
 ## [v0.16.0](https://github.com/thanos-io/thanos/releases) - Release in progress