Merge branch 'update-mattermost-operator-tag-1.20.0-bb.0' into 'master'

mattermostOperator update to 1.20.0-bb.0

Closes big-bang/product/packages/mattermost-operator#26

See merge request !2603

chart/values.yaml

@@ -1246,7 +1246,7 @@ addons:
     git:
       repo: https://repo1.dso.mil/platform-one/big-bang/apps/collaboration-tools/mattermost-operator.git
       path: "./chart"
-      tag: "1.19.0-bb.0"
+      tag: "1.20.0-bb.0"
 
     # -- Flux reconciliation overrides specifically for the Mattermost Operator Package
     flux: {}