site-styles: Remove the unused rule about file description

[Func86]

The shared file description feature has been disabled from the server side, so this rule is unused.

I think it should be enabled though, since nowadays file descriptions are generally proper enough.

[lovelyCARDINAL]

考虑在 mailmap 添加用户名不？

[Func86]

得在 mailmap 补个用户名，不然会报错。

我关机了，你加个还是说我明天来加

---

哦，那没问题的话也可以不加（

[lovelyCARDINAL]

我已经按照commit信息加了，那没事了