Update user details at each login, if necessary

[GabrielMajeri]

We encountered the following situation in production: a user's e-mail account and family name got changed, but their data stayed the same in osTicket (because there's no resync/attribute update mechanism in place).

It's probably a good idea to check each time a user logs in if their MS365 profile data is still up-to-date, and update it accordingly.