fix: k8s client status cond is possible null in podState

Signed-off-by: GlobefishNG <yongcong.ma@neuralgalaxy.com>

modules/nextflow/src/main/groovy/nextflow/k8s/client/K8sClient.groovy

@@ -487,7 +487,7 @@ class K8sClient {
             if( status.conditions instanceof List ) {
                 final allConditions = status.conditions as List<Map>
                 final cond = allConditions.find { cond -> cond.type == 'PodScheduled' }
-                if( cond.reason == 'Unschedulable' ) {
+                if( cond?.reason == 'Unschedulable' ) {
                     def message = "K8s pod cannot be scheduled"
                     if( cond.message ) message += " -- $cond.message"
                     //def cause = new K8sResponseException(resp)