perf(includes): 移除 busuanzi 脚本中的冗余属性

移除了 additional-js.pug 文件中 busuanzi 脚本标签的 data-pjax 属性，
因为 pjax 属性已经存在，冗余的属性可能会导致不必要的性能开销。

themes/butterfly/layout/includes/additional-js.pug

@@ -60,6 +60,6 @@ div
     != partial("includes/third-party/pjax", {}, { cache: true })
 
   if theme.busuanzi.site_uv || theme.busuanzi.site_pv || theme.busuanzi.page_pv
-    script(async data-pjax pjax data-prefix="busuanzi_value" src='https://bsz.iirose.cn/js')
+    script(async pjax data-prefix="busuanzi_value" src='https://bsz.iirose.cn/js')
 
   !=partial('includes/third-party/search/index', {}, {cache: true})