Fix some incorrect links in docs (#28191) (#28201)

Backport #28191 by @yp05327

https://gitea.com/gitea/gitea-docusaurus/actions/runs/661/jobs/0#jobstep-9-39
I noticed that there are many warning logs in building docs.
It is causing 404 in docs.gitea.com now, so we need to fix it.
And there are also some other problems in v1.19 which can not be done in
this PR.

Co-authored-by: yp05327 <576951401@qq.com>
(cherry picked from commit 4b89c0f996)

docs/content/usage/authentication.zh-cn.md

@@ -162,7 +162,7 @@ PAM提供了一种机制，通过对用户进行PAM认证来自动将其添加
     - PAM电子邮件域:用户认证时要附加的电子邮件后缀。例如，如果登录系统期望一个名为gituse的用户，
   并且将此字段设置为mail.com，那么Gitea在验证一个GIT实例的用户时将期望user emai字段为gituser@mail.com[^2]。
 
-**Note**: PAM 支持通过[build-time flags](installation/install-from-source.md#build)添加,
+**Note**: PAM 支持通过[build-time flags](installation/from-source.md#build)添加,
 而官方提供的二进制文件通常不会默认启用此功能。PAM需要确保系统上有必要的libpam动态库，并且编译器可以访问必要的PAM开发头文件。
 
 [^1]: 例如，在Debian "Bullseye"上使用标准Linux登录，可以使用`common-session-noninteractive`。这个值对于其他版本的Debian，