Pre-emptive token refresh mechanism

[FedericoNegri]

Add the ability to monitor the lifetime of auth tokens to pre-emptively refresh them.

This should be a configurable feature, because there can be consumers that want to directly control what happens with those tokens (remember: requesting new tokens can invalidate existing ones).

[ojkoenig]

Bug related to this:
https://github.com/ansys-internal/rep-deployments/issues/3302

[ojkoenig]

Tried your PR quickly on the large MAPDL benchmark models, seems to work, previously failing job uploads are now working...