Fix delete board button not visible.

Thanks to airtraxx and xet7 !

Related #3396

client/components/boards/boardArchive.jade

@@ -7,10 +7,9 @@ template(name="archivedBoards")
     each archivedBoards
       li.archived-lists-item
         div.board-header-btns
-          if currentUser.isBoardAdmin
-            button.board-header-btn.js-delete-board
-              i.fa.fa-trash-o
-              | {{_ 'delete-board'}}
+          button.board-header-btn.js-delete-board
+            i.fa.fa-trash-o
+            | {{_ 'delete-board'}}
           button.board-header-btn.js-restore-board
             i.fa.fa-undo
             | {{_ 'restore-board'}}