Add helpful comment

Signed-off-by: Derek Ho <dxho@amazon.com>

.env

@@ -119,7 +119,7 @@ PROMETHEUS_ADDR=${PROMETHEUS_SERVICE_HOST}:${PROMETHEUS_SERVICE_PORT}
 
 # OpenSearch versionins
 OPENSEARCH_VERSION=2.11.0
-OPENSEARCH_ADMIN_PASSWORD=admin
+OPENSEARCH_ADMIN_PASSWORD=admin # After 2.12.0 release, this needs to be changed to the value passed in as OPENSEARCH_INITIAL_ADMIN_PASSWORD
 
 # OpenSearch Node1
 OPENSEARCH_PORT=9200