fix(route): fix zhihu/zhuanlan route is empty and some answer item do not have question.author field (#8952)

* Fix(route): fix route is empty

* Fix(route): some answer item do not have question.author field

* Fix(route): fix route is empty

lib/routes/zhihu/zhuanlan.js

@@ -14,6 +14,17 @@ module.exports = async (ctx) => {
         },
     });
 
+    const pinnedRes = await got({
+        method: 'get',
+        url: `https://www.zhihu.com/api/v4/columns/${id}/pinned-items`,
+        headers: {
+            ...utils.header,
+            Referer: `https://zhuanlan.zhihu.com/${id}`,
+        },
+    });
+
+    listRes.data.data = listRes.data.data.concat(pinnedRes.data.data);
+
     // 知乎专栏链接存在两种格式, 一种以 'zhuanlan.' 开头, 另一种新增的以 'c_' 结尾
     let url = `https://zhuanlan.zhihu.com/${id}`;
     if (id.search('c_') === 0) {
@@ -41,7 +52,7 @@ module.exports = async (ctx) => {
 
         if (item.type === 'answer') {
             title = item.question.title;
-            author = item.question.author.name;
+            author = item.question.author ? item.question.author.name : '';
             link = `https://www.zhihu.com/question/${item.question.id}/answer/${item.id}`;
             pubDate = new Date(item.created_time * 1000);
         } else if (item.type === 'article') {