Automatic merge from submit-queue (batch tested with PRs 63569, 63918, 63980, 63295, 63989). 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>.

GCE provider: add wrapper for security policy

**What this PR does / why we need it**:
Generated mock interface for beta backend service and security policy as well.

**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
Fixes #NONE 

**Special notes for your reviewer**:
/assign @nicksardo   

**Release note**:

```release-note
NONE
```