gatekeeper update to 3.20.1-bb.1

Package Merge Request

Package Changes

https://repo1.dso.mil/big-bang/product/packages/policy/-/blob/3.20.1-bb.1/CHANGELOG.md

Package MR

big-bang/product/packages/policy!330 (merged)

For Issue

Closes Issue

Upgrade Notices

N/A

Closes #292 (closed)