feat: support workload identity

[cvvz]

What type of PR is this?
/kind feature

What this PR does / why we need it:
The previous implementation of supporting workload identity is to use workload identity to retrieve account key for mounting. Since blobfuse2 has supported workload identity authentication, we can use workload identity to directly mount without retrieving account key.

Which issue(s) this PR fixes:

Fixes #

Requirements:

• uses conventional commit messages
• includes documentation
• adds unit tests
• tested upgrade from previous version

Special notes for your reviewer:

Release note:

feat: support original workload identity for blobfuse2 (without retrieve account key)

[acortelyou]

Really glad to see some progress on this feature!

I know it's WIP so perhaps you're already planning to address, but I wanted to mention that the token audience varies by cloud so that will need to be dynamic or configurable.

eg:

var azureTokenExchange = {
  AzureCloud:         'api://AzureADTokenExchange'
  AzureUSGovernment:  'api://AzureADTokenExchangeUSGov'
  AzureChinaCloud:    'api://AzureADTokenExchangeChina'
}[environment().name]

[cvvz]

I've went through the doc docs/workload-identity-static-pv-mount.md to test with the latest blobfuse2 version v2.4.1 on AKS and checked blobfuse2 and csi driver logs. It worked fine.

I've removed the WIP label.
cc @andyzhangx

[cvvz]

@acortelyou Thanks for your kindly reminder. We will keep the token audience unchanged in this PR. And we are discussing whether it should be changed by cloud. If so, we will file another pr to fix it (not only in blob driver but also azurefile driver).

[cvvz]

/retest

[andyzhangx]

can you add the ut?

[andyzhangx]

pls add the ut in another PR

[andyzhangx]

/lgtm

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: andyzhangx, cvvz

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[andyzhangx]

/retest

[andyzhangx]

/cherrypick release-1.26

[k8s-infra-cherrypick-robot]

@andyzhangx: new pull request created: #1888

In response to this:

/cherrypick release-1.26

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[andyzhangx]

/cherrypick release-1.25

[k8s-infra-cherrypick-robot]

@andyzhangx: new pull request created: #1889

In response to this:

/cherrypick release-1.25

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes-sigs/prow repository.