Further improvement for `201-aks-rbac-dashboard-admin`

### Is there an existing issue for this?

- [X] I have searched the existing issues

### Example Name

201-aks-rbac-dashboard-admin

### Terraform Version

1.3

### Current Behavior

As @zioproto pointed out, the example seems has some issue on role binding.

### Expected Behavior

Please refer to #148 for further details.

### Steps To Reproduce

_No response_

### Anything else?

_No response_

Start with the 201-aks-rbac-dashboard-admin example and read issue #148 for the role-binding details referenced here. Compare the example's current role binding with the expected AKS RBAC behavior; done means the example assigns the intended permissions without the reported issue.

Written by the indexing model from the issue text.