Resolve "Update CODEOWNERS in BigBang"

Package Owner Merge Request

Package Changes

CODEOWNERS list updated to remove @barrywoodtetrate, @zackbutcher, and @cdevarenne, plus add @stas.

MRs associated with this change are required:

• https://repo1.dso.mil/platform-one/big-bang/apps/core/istio-controlplane/-/merge_requests/62
• https://repo1.dso.mil/platform-one/big-bang/apps/core/istio-operator/-/merge_requests/20
• https://repo1.dso.mil/platform-one/big-bang/apps/core/authservice/-/merge_requests/39
• https://repo1.dso.mil/platform-one/big-bang/bigbang/-/merge_requests/671

Once the MR is ready for review also add the status::review label.

Closes #580 (closed)