Add example of Bind DN for Active Directory

[vessd]

• Gitea version (or commit ref): v1.13.2
• Git version: v2.30.0.windows.2
• Operating system:
  • Windows 2012 R2
  • Download gitea-1.13.2-windows-4.0-amd64.exe from release page
  • Run as service
• Database (use [x]):
  • PostgreSQL
  • MySQL
  • MSSQL
  • SQLite
• Can you reproduce the bug at https://try.gitea.io:
  • Yes (provide example URL)
  • No
• Log gist:

Description

Please add an example of Bind DN for Active Directory. For some reason, I was able to generate a request only with this form: <sAMAccountName>@<domain FQDN> (e.g. user1@contoso.com)
Source: https://serverfault.com/a/568709