Create an informative issue (See each section, incomplete templates/issues won't be triaged)

Using the current documentation as a model, please complete the issue template. 

Note: Doc team updates the current version and the two previous versions (n-2). For earlier versions, we will address only high-priority, customer-reported issues for releases in support.

Prerequisite: Start with what we have

Always look at the current documentation to describe the change that is needed. Use the source or portal link for Step 4:

 - Use the Customer Portal: https://access.redhat.com/documentation/en-us/red_hat_advanced_cluster_management_for_kubernetes

 - Use the GitHub link to find the staged docs in the repository: https://github.com/stolostron/rhacm-docs 

Describe the changes in the doc and link to your dev story

Provide info for the following steps:

1. - [x] Mandatory Add the required version to the Fix version/s field.  ACM 2.9.0/MCE 2.4.0

2. - [x] Mandatory Choose the type of documentation change.

      - [x] New topic in an existing section or new section: addon new know issues
      - [x] Update to an existing topic: update managedServiceAccount API version from v1alpha1 to v1beta1 for the existing topics

3. - [ ] Mandatory for GA content:
            
       - [x] Add steps and/or other important conceptual information here: 

• • update managedServiceAccount API version from v1alpha1 to v1beta1 for the existing topics, there is a new v1beta1 version API, v1alpha1 can still be used in ACM 2.9, but will be deprecated in ACM 2.10 and removed in ACM 2.11

1. • 1. https://access.redhat.com/documentation/en-us/red_hat_advanced_cluster_management_for_kubernetes/2.5/html/multicluster_engine/managed-serviceaccount-addon
     2. https://access.redhat.com/documentation/en-us/red_hat_advanced_cluster_management_for_kubernetes/2.5/html/multicluster_engine/apis#serviceaccount-api 
   • known issue 1: when enabling the managed-serviceaccount addon, ManagedClusterAddOn.spec.installNamespace must be "open-cluster-management-agent-addon", other values will be ignored and the managed serviceaccount addon agent will be deployed in the "open-cluster-management-agent-addon" namespace on the managed cluster.
   • known issue 2: "tolerations" and "nodeSelector" configured on the multiclusterengines/multiclusterhubs will not take effect on the managed-serviceaccount agent deployed on the local-cluster/hub. (In most cases, the managed-serviceaccount addon is not needed on the local-cluster), the workaround is to create an addonDeploymentgConfig to set the "tolerations" and "nodeSelector" for the local-cluster managed-serviceaccount agent, then update the managed-serviceaccount ManagedClusterAddon in the local-cluster namespace to use the addontDeploymenConfig we just created. we already have a link for how to use the addonDeploymentConfig CR to configure the "tolerations" and "nodeSelector" for addons: https://dxp-docp-prod.apps.ext-waf.spoke.prod.us-west-2.aws.paas.redhat.com/documentation/en-us/red_hat_advanced_cluster_management_for_kubernetes/2.8/html-single/add-ons/index?lb_target=stage#configure-nodeselector-tolerations-addon 

       - [ ] Add Required access level for the user to complete the task here:
       

       - [ ] Add verification at the end of the task, how does the user verify success (a command to run or a result to see?)
     
     
       - [x] Add link to dev story here: https://issues.redhat.com/browse/ACM-7072

4. - [ ] Mandatory for bugs: What is the diff? Clearly define what the problem is, what the change is, and link to the current documentation: