Add changelog for series per query limit

Signed-off-by: Tyler Reid <[email protected]>

CHANGELOG.md

@@ -18,14 +18,16 @@
   * `cortex_alertmanager_state_persist_failed_total`
 * [ENHANCEMENT] Blocks storage: support ingesting exemplars.  Enabled by setting new CLI flag `-blocks-storage.tsdb.max-exemplars=<n>` or config option `blocks_storage.tsdb.max_exemplars` to positive value. #4124
 * [ENHANCEMENT] Distributor: Added distributors ring status section in the admin page. #4151
+* [ENHANCEMENT] Ingester/Block Storage: Added ingester and block storage support for `max_series_per_query` / `-ingester.max-series-per-query`
+  If cortex is running in chunk mode the series limit is only supported for fetched series from the ingester. If cortex is in blocks mode this
+  this limit is for fetched series from block storage and ingester. #4179
 * [BUGFIX] Purger: fix `Invalid null value in condition for column range` caused by `nil` value in range for WriteBatch query. #4128
 * [BUGFIX] Ingester: fixed infrequent panic caused by a race condition between TSDB mmap-ed head chunks truncation and queries. #4176
 
 ## Blocksconvert
 
 * [ENHANCEMENT] Scanner: add support for DynamoDB (v9 schema only). #3828
 
-
 ## 1.9.0 in progress
 
 * [CHANGE] Fix for CVE-2021-31232: Local file disclosure vulnerability when `-experimental.alertmanager.enable-api` is used. The HTTP basic auth `password_file` can be used as an attack vector to send any file content via a webhook. The alertmanager templates can be used as an attack vector to send any file content because the alertmanager can load any text file specified in the templates list. #4129