Automatic merge from submit-queue

Add jregan to OWNERS for kubectl isolation work.

The kubectl decoupling project (#598) requires many BUILD edits.

Even relatively simple PR's involve many OWNER files, e.g. #46317 involves five.

We plan to script-generate some PRs, and those may involve _hundreds_ of BUILD files.

This project will take many PRs, and collecting all approvals for each will be very time consuming.

**Release note**:
```release-note
NONE
```