move changelog entry to unreleased section

CHANGELOG.md

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 * [CHANGE] Querier: pass query matchers to queryable `IsApplicable` hook. #10256
 * [ENHANCEMENT] Distributor: OTLP receiver now converts also metric metadata. See also https://github.com/prometheus/prometheus/pull/15416. #10168
 * [ENHANCEMENT] Distributor: discard float and histogram samples with duplicated timestamps from each timeseries in a request before the request is forwarded to ingesters. Discarded samples are tracked by the `cortex_discarded_samples_total` metrics with reason `sample_duplicate_timestamp`. #10145
+* [ENHANCEMENT] Distributor: Add native histogram support for `electedReplicaPropagationTime` metric in ha_tracker. #10264
 * [BUGFIX] Distributor: Use a boolean to track changes while merging the ReplicaDesc components, rather than comparing the objects directly. #10185
 * [BUGFIX] Querier: fix timeout responding to query-frontend when response size is very close to `-querier.frontend-client.grpc-max-send-msg-size`. #10154
 
@@ -114,7 +115,6 @@
 * [ENHANCEMENT] Ingester: do not reuse labels, samples and histograms slices in the write request if there are more entries than 10x the pre-allocated size. This should help to reduce the in-use memory in case of few requests with a very large number of labels, samples or histograms. #10040
 * [ENHANCEMENT] Query-Frontend: prune `<subquery> and on() (vector(x)==y)` style queries and stop pruning `<subquery> < -Inf`. Triggered by https://github.com/prometheus/prometheus/pull/15245. #10026
 * [ENHANCEMENT] Query-Frontend: perform request format validation before processing the request. #10093
-* [ENHANCEMENT] Distributor: Add native histogram support for `electedReplicaPropagationTime` metric in ha_tracker #10264
 * [BUGFIX] Fix issue where functions such as `rate()` over native histograms could return incorrect values if a float stale marker was present in the selected range. #9508
 * [BUGFIX] Fix issue where negation of native histograms (eg. `-some_native_histogram_series`) did nothing. #9508
 * [BUGFIX] Fix issue where `metric might not be a counter, name does not end in _total/_sum/_count/_bucket` annotation would be emitted even if `rate` or `increase` did not have enough samples to compute a result. #9508