Fix code style and remove redundant code

src/app/components/shared/content-groups/content-groups.component.html

 <mat-card *ngFor="let contentGroup of contentGroups" (click)="viewContents(contentGroup)">
   <mat-card-header>
     <mat-card-title>
-      <h4 *ngIf="!(contentGroup.name === 'Default')">{{contentGroup.name}}<mat-icon color="accent"
-         matBadge="{{contentGroup.contentIds.length}}" matBadgePosition="after" matBadgeColor="accent"></mat-icon></h4>
-      <h4 *ngIf="contentGroup.name === 'Default'">{{'room-page.default-content-group' | translate}}<mat-icon color="accent"
-         matBadge="{{contentGroup.contentIds.length}}" matBadgePosition="end" matBadgeColor="accent"></mat-icon></h4>
+      <h4 *ngIf="!(contentGroup.name === 'Default')">{{contentGroup.name}}</h4>
+      <h4 *ngIf="contentGroup.name === 'Default'">{{'room-page.default-content-group' | translate}}</h4>
     </mat-card-title>
+    <mat-icon color="accent" matBadge="{{contentGroup.contentIds.length}}" 
+      matBadgePosition="after" matBadgeColor="accent"></mat-icon>
   </mat-card-header>
 </mat-card>

src/app/components/shared/content-groups/content-groups.component.scss

@@ -19,3 +19,7 @@
     box-shadow: 0 12px 16px rgba(0, 0, 0, 0.2);
   }
 }
+
+mat-icon {
+  margin-top: 20px;
+}