update changelog

Signed-off-by: Ben Ye <benye@amazon.com>

CHANGELOG.md

@@ -16,6 +16,7 @@ We use *breaking :warning:* to mark changes that are not backward compatible (re
 - [#7080](https://github.com/thanos-io/thanos/pull/7080) Receive: race condition in handler Close() when stopped early
 - [#7132](https://github.com/thanos-io/thanos/pull/7132) Documentation: fix broken helm installation instruction
 - [#7134](https://github.com/thanos-io/thanos/pull/7134) Store, Compact: Revert the recursive block listing mechanism introduced in https://github.com/thanos-io/thanos/pull/6474 and use the same strategy as in 0.31. Introduce a `--block-discovery-strategy` flag to control the listing strategy so that a recursive lister can still be used if the tradeoff of slower but cheaper discovery is preferred.
+- [#7122](https://github.com/thanos-io/thanos/pull/7122) Store Gateway: Fix lazy expanded postings estimate base cardinality using posting group with remove keys.
 
 ### Added
 - [#7105](https://github.com/thanos-io/thanos/pull/7105) Rule: add flag `--query.enable-x-functions` to allow usage of extended promql functions (xrate, xincrease, xdelta) in loaded rules