feat(电子刊)： 边界值判断

@@ -20,7 +20,9 @@
                         <div class="m-order to-download">如何订阅
                             <i class="iconfont">&#xe614;</i>
                         </div>
+                        {{#if subcribeCount }}
                         <div class="m-buy-info">已有{{subcribeCount}}本订阅</div>
+                        {{/if}}
                     </div>
                     
                     <button class="buy-magazine-now" data-sku="{{sku}}" data-buy="{{buyFlag}}">立即购买</button>