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>.

Add ravi to sig scheduling approvers

**What this PR does / why we need it**:
According to the requirement of Approver at community-membership.md, I meet the following requirements so I'd like to add myself as an approver of scheduler.

I have :

- Authored more than ~40 commits to k/k repository and 22 commits in kube-incubator/descheduler.
- Been co-maintainer on descheduler.
- Been a reviewer for more than 3 months.
- Reviewed/helped in reviewing more than 70 PRs.
- Been helping new contributors in getting upto speed and guide them on performance aspects of the kube-scheduler.

As an approver,

-   I agree to only approve familiar PRs
-   I agree to be responsive to review/approve requests as per community expectations
-   I agree to continue my reviewer work as per community expectations
-   I agree to continue my contribution, e.g. PRs, mentor contributors


```release-note
NONE
```

/cc @bsalamat @k82cn @aveshagarwal