Automatic merge from submit-queue. If you want to cherry-pick this change to another branch, please follow the instructions here: https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md.

Update default etcd server to 3.2.24 for kubernetes 1.12

**What this PR does / why we need it**:
Update default etcd server to 3.2.24 for kubernetes 1.12

**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
xref #68147 

**Special notes for your reviewer**:
NONE

**Release note**:

```
Update default etcd server to 3.2.24 for kubernetes 1.12
```

/assign @wojtek-t @jpbetz @dims 
/cc @kubernetes/sig-cluster-lifecycle-pr-reviews @gyuho