Set cert mgr installation disable by default

Author: Xin Wang

helm_chart/HyperPodHelmChart/values.yaml

@@ -116,7 +116,7 @@ namespace:
   name: aws-hyperpod
 
 cert-manager:
-  enabled: true
+  enabled: false
   namespace: cert-manager
   global:
     leaderElection:

helm_chart/readme.md

@@ -33,7 +33,7 @@ More information about orchestration features for cluster admins [here](https://
 | [Kubeflow Training Operator](https://www.kubeflow.org/docs/components/trainer/legacy-v1/overview/)            | Installs operators for managing various machine learning training jobs, such as TensorFlow, PyTorch, and MXNet, providing native Kubernetes support for distributed training workloads. |              | Yes               |
 | HyperPod patching            | Deploys the RBAC and controller resources needed for orchestrating rolling updates and patching workflows in SageMaker HyperPod clusters. Includes pod eviction and node monitoring.    | HyperPod Resiliency             | Yes               |
 | hyperpod-inference-operator  | Installs the HyperPod Inference Operator and its dependencies to the cluster, allowing cluster deployment and inferencing of JumpStart, s3-hosted, and FSx-hosted models                | No                | 
-| [cert-manager](https://github.com/cert-manager/cert-manager)                | Automatically provisions and manages TLS certificates in Kubernetes clusters. Provides certificate lifecycle management including issuance, renewal, and revocation for secure communications. | [Hyperpod training operator](https://docs.aws.amazon.com/sagemaker/latest/dg/sagemaker-eks-operator.html)           | Yes                |
+| [cert-manager](https://github.com/cert-manager/cert-manager)                | Automatically provisions and manages TLS certificates in Kubernetes clusters. Provides certificate lifecycle management including issuance, renewal, and revocation for secure communications. | [Hyperpod training operator](https://docs.aws.amazon.com/sagemaker/latest/dg/sagemaker-eks-operator.html)           | No                |
 
 > **_Note_** The `mpijob` scheme is disabled in the Training Operator helm chart to avoid conflicting with the MPI Operator.