fix(spider):为发布时间提取添加异常处理

当无法正确提取发布时间空时，设置默认值以避免程序中断

spiders/ai_seo/metaso.py

@@ -78,9 +78,12 @@ class MetasoSpider(AbstractAiSeoSpider):
                 # 抽取链接和标题
                 a = search_item.locator("xpath=./div[1]/a")
                 # 抽取时间
+                try:
                     publish_date_element = search_item.locator("xpath=./div[2]/div")
                     publish_str = await publish_date_element.text_content()
                     search_result.publish_time = publish_str.replace('[', '').replace(']', '')
+                except Exception as e:
+                        search_result.publish_time = ''
                 if await a.is_visible():
                     search_result.title = await a.text_content()
                     search_result.url = await a.get_attribute('href')