Update backward_compatibility_test.go

Also updating CHANGELOG with release date for 1.19.0

Signed-off-by: Charlie Le <[email protected]>

Author: CharlieTLe

CHANGELOG.md

@@ -19,7 +19,7 @@
 * [BUGFIX] Query Frontend: Fix samples scanned and peak samples query stats when query hits results cache. #6591
 * [BUGFIX] Query Frontend: Fix panic caused by nil pointer dereference. #6609
 
-## 1.19.0 in progress
+## 1.19.0 2025-02-27
 
 * [CHANGE] Deprecate `-blocks-storage.tsdb.wal-compression-enabled` flag (use `blocks-storage.tsdb.wal-compression-type` instead). #6529
 * [CHANGE] OTLP: Change OTLP handler to be consistent with the Prometheus OTLP handler. #6272

integration/backward_compatibility_test.go

@@ -75,6 +75,7 @@ var (
 		"quay.io/cortexproject/cortex:v1.17.1": nil,
 		"quay.io/cortexproject/cortex:v1.18.0": nil,
 		"quay.io/cortexproject/cortex:v1.18.1": nil,
+		"quay.io/cortexproject/cortex:v1.19.0": nil,
 	}
 )