An error occurred when init k8s object in v1 api

[Yi Feng]

When instantiate CNF resources whose manifest file contains `exec` parameter with v1 api, an error occurred when init k8s object.
The log is shown below.
```
Apr 22 21:36:17 Tacker-On-VM2 tacker-conductor[964844]: 2022-04-22 21:36:17.546 ERROR tacker.vnfm.infra_drivers.kubernetes.k8s.translate_outputs [req-4d4deaf8-afaa-4fae-a2d7-d48a767350b6 admin admin] Deployment create failure. Reason=can only concatenate str (not "NoneType") to str
Apr 22 21:36:17 Tacker-On-VM2 tacker-conductor[964844]: 2022-04-22 21:36:17.546 ERROR tacker.vnflcm.vnflcm_driver [req-4d4deaf8-afaa-4fae-a2d7-d48a767350b6 admin admin] Unable to instantiate vnf instance c1c162d4-bc61-484b-a774-f3a6caee4cc8 due to error : Failed to init resource.: tacker.common.exceptions.InitApiFalse: Failed to init resource.
```

part of yaml_file:
```
       livenessProbe:
          exec:
            command:
            - rm
            - -f
            - /usr/local/container/CheckFile.txt

```

In the manifest file, there is an `exec` parameter, but in the kubernetes-client module, this parameter is modified to `_exec` due to the need to avoid python keywords. This processing resulted in an unrecognized `exec` parameter in the manifest file, which resulted in an error.
The following resources were found to have the same problem during the investigation.
1. `_not` of V1JsonSchemaProps
2. `_except` of V1IPBlock
3. `_continue` of V1ListMeta
4. `_from` of V1NetworkPolicyIngressRule
5. `_exec` of V1LifecycleHandler

In order to solve this problem, it is necessary to convert the above keywords into keywords that can be recognized by the kubernetes-client module.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.opendev.org/c/openstack/tacker/+/845655

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.opendev.org/c/openstack/tacker/+/845655
Committed: https://opendev.org/openstack/tacker/commit/6441914c5fa46c12b16e5545956f5a0494f07874
Submitter: "Zuul (22348)"
Branch: master

commit 6441914c5fa46c12b16e5545956f5a0494f07874
Author: Shuwen Cai <email address hidden>
Date: Tue Jun 14 11:08:31 2022 +0900

    Fix k8s init error when file contains special key

    When executing CNF lifcycle operations, if the manifest file
    contains the following parameters:
      `exec`, `not`, `except`, `continue`, `from`
    the initialization of Kubernetes resources will fail.

    To fix this issue, this patch makes changes to the `_init_k8s_obj`
    method in the `translate_outputs.py` file. When the manifest file
    contains the above parameters, it is first converted into
    parameters that can be recognized by the k8s client module and
    then initialized.

    Closes-Bug: #1978071
    Change-Id: I392e1b07152b260de775754dbe4606995f658d8d

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/tacker 8.0.0.0rc1 release candidate.