DD message area chooser: Updated to try to prevent an "undefined" error when only choosing a sub-board within the user's current message group

DD message area chooser: Updated to try to prevent the error "this.subBoardListPrintfInfo[pGrpIdx] is undefined" when only choosing a sub-board within the user's current message group.

enabled an automatic merge when the pipeline for b94cba8c succeeds

Is the sexpots build job stuck? It looks like it has been running for 41 minutes so far: https://gitlab.synchro.net/main/sbbs/-/jobs/36360

merged

mentioned in commit dde8c68d