Automatic merge from submit-queue (batch tested with PRs 59052, 59157, 59428, 59949, 60151). 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>.

svcacct: default expiration of TokenRequest

* default expiration seconds to 1 hour

```release-note
NONE
```