K8s: use joinable manager queues (apache#63789)

The executor already treats both queues as joinable queues. It calls:
  - task_done()
  - join()
  - flush logic that assumes task accounting is tracked

A plain manager Queue() does not match that contract. On Python 3.14 this showed up in teardown/error paths as: `ValueError: task_done() called too many times`

Author: Dev-iL

providers/cncf/kubernetes/src/airflow/providers/cncf/kubernetes/executors/kubernetes_executor.py

@@ -103,8 +103,8 @@ def __init__(self, *args, **kwargs):
         self.parallelism = self.kube_config.parallelism
 
         self._manager = multiprocessing.Manager()
-        self.task_queue: Queue[KubernetesJob] = self._manager.Queue()
-        self.result_queue: Queue[KubernetesResults] = self._manager.Queue()
+        self.task_queue: Queue[KubernetesJob] = self._manager.JoinableQueue()
+        self.result_queue: Queue[KubernetesResults] = self._manager.JoinableQueue()
         self.kube_scheduler: AirflowKubernetesScheduler | None = None
         self.kube_client: client.CoreV1Api | None = None
         self.scheduler_job_id: str | None = None