Automatic merge from submit-queue (batch tested with PRs 67347, 67307, 67358, 67364, 67385). 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>.

use temp file for kubeconfig in test

Followup to https://github.com/kubernetes/kubernetes/pull/67093

Updates client_config_test to use a temporary file for kubeconfig.

**Release note**:
```release-note
NONE
```

cc @deads2k @soltysh