Add namespace name in ServiceAccount view with RoleBinding

[vladfr]

Describe the bug
In the ServiceAccount view (hit ENTER) you see NAMESPACE "*" for a ClusterRole bound with a RoleBinding.

To Reproduce
Steps to reproduce the behavior:

1. Get a default kind cluster
2. Create a RoleBinding for the built-in CR:View ClusterRole

kubectl create rolebinding view \
  --clusterrole=view \
  --serviceaccount=default:default \
  --namespace=default

3. Open k9s and search for :serviceaccount. Find default:default and hit Enter.
4. See the list of RBACs, see that the Namespace column has *, when in fact it should have default.

Expected behavior
The NAMESPACE column should have the namespace that was used in the RoleBinding.

Versions (please complete the following information):

• OS: OSX
• K9s: 0.27.4
• K8s: 1.27.3 kind

Additional context
Even though this is a ClusterRole, because it's bound using a RoleBinding, it only gives permissions to resources from a namespace. When debugging RBAC, this can be confusing.

[vladfr]

If it makes sense to fix this, I would absolutely like to submit a PR as well. It would be my first contribution to k9s so it's why I'm starting with opening an issue.

edit: well this turned out to be an easy fix. Check out the PR! 🌞