Fixed Duplicate board.

Thanks to Ben0it-T and xet7 !

Fixes #4260

client/components/boards/boardsList.js

@@ -241,6 +241,7 @@ BlazeComponent.extendComponent({
                 this.setError(err.error);
               } else {
                 Session.set('fromBoard', null);
+                subManager.subscribe('board', res, false);
                 Utils.goBoardId(res);
               }
             },

client/components/lists/listBody.js

@@ -714,6 +714,7 @@ BlazeComponent.extendComponent({
               },
               (err, data) => {
                 _id = data;
+                subManager.subscribe('board', _id, false);
               },
             );
           }

models/boards.js

@@ -623,6 +623,7 @@ Boards.helpers({
       rule.triggerId = triggersMap[rule.triggerId];
       Rules.insert(rule);
     });
+    return _id;
   },
   /**
    * Return a unique title based on the current title