message: Fix unit switch case
diff: matTooltip="{{getFormattedDeadline(unit.deadline)}}">
  {{getDeadlineDiffText(unit.deadline)}}<strong>{{getDeadlineDiffTime(unit.deadline)}}</strong>
  </span>
  - <mat-card-content [ngSwitch]="unit">
  + <mat-card-content [ngSwitch]="unit.type">
  <app-video-unit *ngSwitchCase="'video'" [videoUnit]="unit"></app-video-unit>
  <app-file-unit *ngSwitchCase="'file'" [fileUnit]="unit"></app-file-unit>
  <app-task-unit *ngSwitchCase="'task'" [taskUnit]="unit"></app-task-unit>
  