Update together (Threepid and Displayname) at each login

[odelcroi]

Currently, the update of the threepid (email) only works at first proconnect login :

• if oidc identity is matched to a threepid that differs from email claims, the threepid is updated.

In my opinion, it causes confusion for the user :

• as the threepid is used for legacy login, after the threepid is updated, the user must use the new threepid for legacy login
• it is hard to explain that this happens
• it is hard for the user to remember
• it is hard for the user to understand that this replacement only happens at the first oidc login

Thus I would recommend to switch off the actuel threepid replacement mecanism and implement another logic :

• anytime after a oidc login, if oidc identity is matched to a threepid that differs from email claims, the threepid is updated AND the display name is updated too

-> users have a visual feedback that their threepid has been updated thanks to the display name
-> as it happens anytime, it helps understanding

This can be achieved with the synapse option : update_profile_information

Todo :

• rollback module deployment before this PR : When first proconnect login, update threepid email if needed #1
• update new logic with using update_profile_information capabilities