[skip e2e] Add memory stress test scenarious in chaos readme (#14397)

Signed-off-by: NThreadDao <yufen.zong@zilliz.com>

tests/python_client/chaos/README.md

@@ -33,6 +33,8 @@ Set the pod（querynode, indexnode and datanode）as multiple replicas, make one
 
 #### pod memory stress
 
+Limit the memory resource of pod and generate plenty of stresses over a group of pods
+
 ### Milvus in standalone mode
 1. standalone pod is killed