Add Back button to comments

apps/twitch-logs/src/app/comments/comments.component.html

@@ -10,6 +10,8 @@
 
         <span class="spacer"></span>
 
+        <button class="export-button" color="primary" mat-raised-button [routerLink]="['/']">Back</button>
+
     </mat-toolbar>
 
     <div class="spinner-container" *ngIf="dataSource.loading$ | async">