Draft: mattermost update to 9.4.2-bb.1

Package Merge Request

Package Changes

https://repo1.dso.mil/big-bang/product/packages/mattermost/-/blob/9.4.2-bb.1/CHANGELOG.md

Package MR

big-bang/product/packages/mattermost!183 (merged)

For Issue

Closes (link to issue here)

Upgrade Notices

The db probe init container will not be included if istio is hardened, this shouldn't cause any issues, but it should be noted.