Automatic merge from submit-queue (batch tested with PRs 55594, 47849, 54692, 55478, 54133). If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.
add kubeadm alpha phase kubeconfig option(--output)
**What this PR does / why we need it**:
This PR will add --output option to `kubeadm alpha phase kubeconfig [command]`
This option can change output directory of kubeconfig.
Prev: kubeadm alpha phase kubeconfig admin
we can get admin.conf in /etc/kubernetes/ .
This PR: kubeadm alpha phase kubeconfig admin --output /root
we can get admin.conf in /root/ .
Of course, --output is optional.(default directory is /etc/kubernetes)
Note)
I have no confidence about my test code.
Thank you.
**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes #
**Special notes for your reviewer**:
**Release note**:
```release-note
```
81fa823a6c