Enable proactive renewal of Managed Identity tokens

[joshfree]

Intro:
Refreshing the tokens with half lifetime would improve resiliency for clients if there's an ESTS outage while fetching a token.

Acceptance Criteria:
All MSI tokens are refreshed at least half lifetime token request is made after half lifetime

MSI has token lifetime of 24 hours. Refresh the tokens if refresh_in is passed from ESTS or at half lifetime if refresh_in isn't passed. For tokens which have lifetime of less than 2 hours, there are no changes to be made.

[joshfree]

This item is actionable for C++. @billwert could you please share the PR from Java?

[billwert]

the first part: Azure/azure-sdk-for-java#33766

the bug fix I had to make :) Azure/azure-sdk-for-java#33970

[antkmsft]

// NOTE: To person who might be fixing this, look at TokenRequestContext::MinimumExpiration maybe utilizing it would help.

[antkmsft]

Or, maybe in GetToken(), simply cut the expiration in half when it is >24 hours, see the other SDKs for inspiration.