authenticate token each time client is sending request

[VeryEarly]

Description

#11925
#6585

Added delegate function to RenewingTokenCredential when management client was instantiated.

This function will authenticate token (refresh if expired) each time ProcessHttpRequestAsync was called.

ProcessHttpRequestAsync will be executed before management client tries to send request (include polling for long running operation)
https://github.com/Azure/azure-sdk-for-net/blob/master/sdk/mgmtcommon/ClientRuntime.Azure/ClientRuntime.Azure/LRO/LROPollState.cs#L182

Checklist

• I have read the Submitting Changes section of CONTRIBUTING.md
• The title of the PR is clear and informative
• The appropriate ChangeLog.md file(s) has been updated:
  • For any service, the ChangeLog.md file can be found at src/{{SERVICE}}/{{SERVICE}}/ChangeLog.md
  • A snippet outlining the change(s) made in the PR should be written under the ## Upcoming Release header -- no new version header should be added
• The PR does not introduce breaking changes
• If applicable, the changes made in the PR have proper test coverage
• For public API changes to cmdlets:
  • a cmdlet design review was approved for the changes in this repository (Microsoft internal only)
  • the markdown help files have been regenerated using the commands listed here

[isra-fel]

Thinking about the different login scenarios: interactive, service principal, managed service identity, they use different mechanism to refresh token. We need test them all.
Forget it. This issue is all about access token scenario.

[markcowl]

One minor comment. Also, what validation are we planning to do here?

[VeryEarly]

One minor comment. Also, what validation are we planning to do here?

1. I'll debug a long running operation see whether it was a new token (from context.account.accesstoken)

2. provide engineering build to partner (who reported this issue), ask them to help verify (meanwhile I'll try to reproduce more than one hour long running operations in my local)

[isra-fel]

/azp run azure-powershell - powershell-core

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