**Apache Airflow version**: 2.0.1


**Kubernetes version (if you are using kubernetes)** (use `kubectl version`): 1.18

**Environment**: GKE

- **Cloud provider or hardware configuration**: GKE on GCP
- **OS** (e.g. from /etc/os-release): Debian 10
- **Kernel** (e.g. `uname -a`): 5.4.89+

**What happened**:

When executing a KuberentesPodOperator with `is_delete_operator_pod=True`, if the Pod doesn't complete successfully, then a 404 error is raised when attempting to get the final pod status.  This doesn't cause any major operational issues to us as the Task fails anyway, however it does cause confusion for our users when looking at the logs for their failed runs.

```
Traceback (most recent call last):
  File "/usr/local/lib/python3.8/site-packages/airflow/models/taskinstance.py", line 1112, in _run_raw_task
    self._prepare_and_execute_task_with_callbacks(context, task)
  File "/usr/local/lib/python3.8/site-packages/airflow/models/taskinstance.py", line 1285, in _prepare_and_execute_task_with_callbacks
    result = self._execute_task(context, task_copy)
  File "/usr/local/lib/python3.8/site-packages/airflow/models/taskinstance.py", line 1310, in _execute_task
    result = task_copy.execute(context=context)
  File "/usr/local/lib/python3.8/site-packages/airflow/providers/cncf/kubernetes/operators/kubernetes_pod.py", line 341, in execute
    status = self.client.read_namespaced_pod(self.pod.metadata.name, self.namespace)
  File "/usr/local/lib/python3.8/site-packages/kubernetes/client/apis/core_v1_api.py", line 18446, in read_namespaced_pod
    (data) = self.read_namespaced_pod_with_http_info(name, namespace, **kwargs)
  File "/usr/local/lib/python3.8/site-packages/kubernetes/client/apis/core_v1_api.py", line 18524, in read_namespaced_pod_with_http_info
    return self.api_client.call_api('/api/v1/namespaces/{namespace}/pods/{name}', 'GET',
  File "/usr/local/lib/python3.8/site-packages/kubernetes/client/api_client.py", line 330, in call_api
    return self.__call_api(resource_path, method,
  File "/usr/local/lib/python3.8/site-packages/kubernetes/client/api_client.py", line 163, in __call_api
    response_data = self.request(method, url,
  File "/usr/local/lib/python3.8/site-packages/kubernetes/client/api_client.py", line 351, in request
    return self.rest_client.GET(url,
  File "/usr/local/lib/python3.8/site-packages/kubernetes/client/rest.py", line 227, in GET
    return self.request("GET", url,
  File "/usr/local/lib/python3.8/site-packages/kubernetes/client/rest.py", line 222, in request
    raise ApiException(http_resp=r)
kubernetes.client.rest.ApiException: (404)
Reason: Not Found
```

**What you expected to happen**:

A 404 error should not be raised - the pod should either be deleted after the state is retrieved, or the final_state returned from `create_new_pod_for_operator` should be used.

**How to reproduce it**:
Run A KubernetesPodOperator that doesn't result Pod with state SUCCESS with `is_delete_operator_pod=True` 

**Anything else we need to know**:
This appears to have been introduced here: https://github.com/apache/airflow/pull/11369 by adding:
```
status = self.client.read_namespaced_pod(self.pod.metadata.name, self.namespace)
```
if the pod state != SUCCESS

airflow/providers/cncf/kubernetes/operators/kubernetes_pod.py
:param volume_mounts: volumeMounts for launched pod.
    :type volume_mounts: list[k8s.V1VolumeMount]
    :param volumes: volumes for launched pod. Includes ConfigMaps and PersistentVolumes.
    :type volumes: list[k8s.V1Volume]
    :param env_vars: Environment variables initialized in the container. (templated)
    :type env_vars: list[k8s.V1EnvVar]
    :param secrets: Kubernetes secrets to inject in the container.
        They can be exposed as environment vars or files in a volume.
    :type secrets: list[airflow.kubernetes.secret.Secret]
    :param in_cluster: run kubernetes client with in_cluster configuration.
    :type in_cluster: bool
    :param cluster_context: context that points to kubernetes cluster.
        Ignored when in_cluster is True. If None, current-context is used.
    :type cluster_context: str
    :param reattach_on_restart: if the scheduler dies while the pod is running, reattach and monitor
    :type reattach_on_restart: bool
    :param labels: labels to apply to the Pod. (templated)
    :type labels: dict
    :param startup_timeout_seconds: timeout in seconds to startup the pod.
    :type startup_timeout_seconds: int
    :param get_logs: get the stdout of the container as logs of the tasks.
    :type get_logs: bool
    :param image_pull_policy: Specify a policy to cache or always pull an image.
    :type image_pull_policy: str
    :param annotations: non-identifying metadata you can attach to the Pod.
        Can be a large range of data, and can include characters
        that are not permitted by labels.
    :type annotations: dict
    :param resources: A dict containing resources requests and limits.
        Possible keys are request_memory, request_cpu, limit_memory, limit_cpu,