upcoming: [M3-10780] - prepare for LKE Dashboard removal

Do not show LKE Dashboard button if the dashboard is missing.

https://techdocs.akamai.com/cloud-computing/docs/an-overview-of-the-kubernetes-dashboard-on-lke

LKE’s Kubernetes Dashboard will be decommissioned in May 2026

Following the upstream archival of the Kubernetes Dashboard project,
Akamai Cloud will decommission the LKE-hosted Kubernetes Dashboard. This
change will occur in May 2026. Once decommissioned, the Kubernetes
Dashboard UI will no longer be available for new and existing LKE
clusters.

Author: isimluk

packages/manager/src/features/Kubernetes/KubernetesClusterDetail/KubeSummaryPanel.tsx

@@ -166,7 +166,7 @@ export const KubeSummaryPanel = React.memo((props: Props) => {
                 <ActionMenu
                   actionsList={[
                     {
-                      disabled: Boolean(dashboardError) || !dashboard,
+                      disabled: Boolean(dashboardError) || !dashboard || !dashboard.url,
                       onClick: () => window.open(dashboard?.url, '_blank'),
                       title: 'Kubernetes Dashboard',
                     },
@@ -183,7 +183,7 @@ export const KubeSummaryPanel = React.memo((props: Props) => {
                 cluster.tier === 'enterprise' ? undefined : (
                   <StyledActionButton
                     disabled={
-                      Boolean(dashboardError) || !dashboard || isClusterReadOnly
+                      Boolean(dashboardError) || !dashboard || !dashboard.url || isClusterReadOnly
                     }
                     endIcon={<ExternalLinkIcon sx={{ height: '14px' }} />}
                     onClick={() => window.open(dashboard?.url, '_blank')}