In the v2.2.0 version (~year 2021) of the default installation (https://raw.githubusercontent.com/kubernetes/dashboard/v2.2.0/aio/deploy/recommended.yaml), they use kubernetes-dashboard as the namespace.
The command would look like this:
kubectl edit deployment kubernetes-dashboard -n kubernetes-dashboard
The change would look like this:
# ... content before...
spec:
containers:
- args:
- --auto-generate-certificates
- --namespace=kubernetes-dashboard
- --token-ttl=0 # <-- add this with your timeout
image: kubernetesui/dashboard:v2.0.0
# ... content after ...
As TJ Zimmerman suggested: 0 = no-timeout.