[release] Update image version (#2590)

Author: julianocosta89

.env

@@ -1,5 +1,5 @@
 # Demo App version
-IMAGE_VERSION=2.1.0
+IMAGE_VERSION=2.1.1
 IMAGE_NAME=ghcr.io/open-telemetry/demo
 DEMO_VERSION=latest
 

CHANGELOG.md

@@ -7,6 +7,8 @@ the release.
 
 ## Unreleased
 
+## 2.1.1
+
 * Align env vars
   ([#2582](https://github.com/open-telemetry/opentelemetry-demo/pull/2582))
 * [opensearch] Reduce OpenSearch container memory footprint