**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
log_line += f"creating pod with labels {labels} and launcher {launcher}"
            self.log.info(log_line)
            final_state, _, result = self.create_new_pod_for_operator(labels, launcher)
        return final_state, result
    @staticmethod
    def _get_pod_identifying_label_string(labels) -> str:
        filtered_labels = {label_id: label for label_id, label in labels.items() if label_id != 'try_number'}
        return ','.join(label_id + '=' + label for label_id, label in sorted(filtered_labels.items()))
    @staticmethod
    def _try_numbers_match(context, pod) -> bool:
        return pod.metadata.labels['try_number'] == context['ti'].try_number
    def _set_name(self, name):
        if name is None:
            if self.pod_template_file or self.full_pod_spec:
                return None
            raise AirflowException("`name` is required unless `pod_template_file` or `full_pod_spec` is set")
        validate_key(name, max_length=220)
        return re.sub(r'[^a-z0-9.-]+', '-', name.lower())
    def create_pod_request_obj(self) -> k8s.V1Pod:
        """
        Creates a V1Pod based on user parameters. Note that a `pod` or `pod_template_file`
        will supersede all other values.
        """
        self.log.debug("Creating pod for KubernetesPodOperator task %s", self.task_id)
        if self.pod_template_file:
            self.log.debug("Pod template file found, will parse for base pod")
            pod_template = pod_generator.PodGenerator.deserialize_model_file(self.pod_template_file)
            if self.full_pod_spec:
                pod_template = PodGenerator.reconcile_pods(pod_template, self.full_pod_spec)
        elif self.full_pod_spec: