Add section header for 'How Litmus works?' (#387)

Signed-off-by: Aditya Ray <96347576+adi-ray@users.noreply.github.com>

Author: adi-ray

website/docs/architecture/architecture-summary.md

@@ -14,6 +14,8 @@ The Litmus architecture can be segregated into two parts:
 
 2. **Execution plane:** Contains the components required for the injection of chaos in the target resources.
 
+## How Litmus works?
+
 - Control plane can be used for creating and scheduling chaos experiments, which is a set of chaos faults defined in a definitive sequence to achieve desired chaos impact on the target resources upon execution. Users can log in to the ChaosCenter using the web UI or the APIs to define a chaos experiment and assess the resilience of target workloads.
 
 - Once the user creates a chaos experiment using the ChaosCenter, it is passed on to the execution plane. The Execution plane can be present either in the same cluster as the ChaosCenter if the self chaos infrastructure is being used, or in a remote cluster if an external chaos infrastructure is being used. The Execution plane interprets the chaos experiment as a list of actions that will inject chaos into the target workloads. It ensures efficient orchestration of chaos in various cloud-native environments using Kubernetes custom resources.