Automatic merge from submit-queue. 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>.
Updates kubeadm default to use 1.10
**What this PR does / why we need it**:
In line with https://github.com/kubernetes/kubeadm/blob/master/docs/release-cycle.md, the default branch for kubeadm to deploy should be bumped right before the rc.1.
This can even be manually merged by the someone from the release team.
**Which issue(s) this PR fixes** :
Fixes#60608
**Special notes for your reviewer**:
**Release note**:
```
Updates default deployment for kubeadm to 1.10
```
/cc @kubernetes/sig-cluster-lifecycle-pr-reviews @kubernetes/sig-release-members @dims @jberkus @jdumars
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