Fix CHANGELOG entry

Signed-off-by: Marco Pracucci <[email protected]>

Author: pracucci

CHANGELOG.md

@@ -9,7 +9,7 @@
   - Alerts: added "CortexBucketIndexNotUpdated" (bucket index only) and "CortexTenantHasPartialBlocks"
 * [ENHANCEMENT] The name of the overrides configmap is now customisable via `$._config.overrides_configmap`. #244
 * [ENHANCEMENT] Added flag to control usage of bucket-index, and enable it by default when using blocks. #254
-* [ENHANCEMENT] Added the alert `CortexIngesterHasUnshippedBlocks`. #248
+* [ENHANCEMENT] Added the alert `CortexIngesterHasUnshippedBlocks`. #255
 * [BUGFIX] Honor configured `per_instance_label` in all panels. #239
 * [BUGFIX] `CortexRequestLatency` alert now ignores long-running requests on query-scheduler. #242
 * [BUGFIX] Honor configured `job_names` in the "Memory (go heap inuse)" panel. #247