Fix broken duplicate link (CATcher-org#1233)

Fix the broken link of a duplicate issue

Currently, the user cannot open the link to a duplicate issue
when opening an issue, as described in CATcher-org#1228.

The links now work as expected.

src/app/shared/issue/duplicatedIssues/duplicated-issues.component.html

@@ -8,7 +8,7 @@
       matTooltipPosition="above"
       (removed)="removeDuplicateStatus(duplicatedIssue)"
     >
-      <a class="no-underline link-grey-dark" [routerLink]="['./' + duplicatedIssue.id]"> #{{ duplicatedIssue.id }} </a>
+      <a class="no-underline link-grey-dark" [routerLink]="['../' + duplicatedIssue.id]"> #{{ duplicatedIssue.id }} </a>
       <mat-icon *ngIf="permissions.isTeamResponseEditable() || permissions.isTutorResponseEditable()" matChipRemove>cancel</mat-icon>
     </mat-chip>
   </mat-chip-list>