OIDC: pre-OIDC devices have incorrect `last_seen_ts`

[kerryarchibald]

Description

element.io sessions authenticated before SSO was enabled have incorrect last_seen_ts

Steps to reproduce

• Have an existing element.io device, authenticated via user/pass before SSO was enabled for element.io
• GET /v3/devices, and see that this device has a last_seen_ts: 1688108976491 (June 30), despite being currently active

Homeserver

https://element.ems.host/

Synapse Version

{"server_version":"1.92.3","python_version":"3.11.5"}

Installation Method

I don't know

Database

na

Workers

I don't know

Platform

.

Configuration

No response

Relevant log output

.

Anything else that would be useful to know?

No response

[clokep]

Is this different than #16084?

[reivilibre]

seems like a dupe of #16084 to me