Mattermost upgrade 6 3 3

Package Merge Request

Package Change

Upgrade Mattermost to appVersion 6.3.3 chart version 0.5.0-bb.0

Package MR

https://repo1.dso.mil/platform-one/big-bang/apps/collaboration-tools/mattermost/-/merge_requests/77

For Issue

closes https://repo1.dso.mil/platform-one/big-bang/apps/collaboration-tools/mattermost/-/issues/38

Package release

https://repo1.dso.mil/platform-one/big-bang/apps/collaboration-tools/mattermost/-/releases/0.5.0-bb.0