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>.
Build Kubernetes binaries with valid Semantic Version
**What this PR does / why we need it**:
Refuse to build Kubernetes when a version string like `v1.8.3+xx+xx`.
This PR is to restrict the `KUBE_GIT_VERSION`, if the version string does match the rule of Semantic Version, then refuse to build.
Since Kubernetes Conformance test needs the `KUBE_GIT_VERSION` to be a valid Semantic Version, so I think it's better to restrict the version string.
**Release note**:
```release-note
NONE
```