feat: stabilize drift for ske egress range (#971)

* feat: stabilize drift for ske egress range

* feat: add PlanModifiers to pod_address_ranges too

Author: mitterle-sit

stackit/internal/services/ske/cluster/resource.go

@@ -372,11 +372,17 @@ func (r *clusterResource) Schema(_ context.Context, _ resource.SchemaRequest, re
 				Description: "The outgoing network ranges (in CIDR notation) of traffic originating from workload on the cluster.",
 				Computed:    true,
 				ElementType: types.StringType,
+				PlanModifiers: []planmodifier.List{
+					listplanmodifier.UseStateForUnknown(),
+				},
 			},
 			"pod_address_ranges": schema.ListAttribute{
 				Description: "The network ranges (in CIDR notation) used by pods of the cluster.",
 				Computed:    true,
 				ElementType: types.StringType,
+				PlanModifiers: []planmodifier.List{
+					listplanmodifier.UseStateForUnknown(),
+				},
 			},
 			"node_pools": schema.ListNestedAttribute{
 				Description: "One or more `node_pool` block as defined below.",