Teams SSH doesn't update existing users' SSH keys

首先定位 teams-ssh 的更新迴圈，以及讀取 Github 團隊成員關係和使用者 SSH 金鑰的程式碼。確認現有使用者在 authorized_keys 中的表示方式，然後將完成條件定義為：能夠偵測並加入新增加的金鑰，而不需要變更團隊成員關係；金鑰移除明確留作設計問題。

If someone is added to the Sudo or SSH teams in the HacKSU org, and later adds SSH key(s) to their account in order to log in to a server, the new keys will not be added to their .ssh/authorized_keys file, since that file is only updated when the user account is initially added to the server.

This can be worked around by removing a user from both the SSH and, if necessary, the Sudo team, waiting for teams-ssh to update, and then re-adding them and waiting for teams-ssh to update again.

Fixing this would require pulling each user's SSH keys along with their team membership from Github every 60 seconds, checking if each key is already present in the authorized_keys file or not, and adding it if it isn't already there.

Automatically removing keys when they're removed from a user's Github profile could be more problematic. It would increase the security of the system by providing a quick way to remove keys if they're compromised, but it could also lead to unexpected lockouts if the user uses an SSH key for their server account without even realizing it's also saved in their Github account.