producer using oauth_cb with azure identity

[vedrank]

What

Adding producer example which is using oauth callback function with azure managed identity

Checklist

None

References

JIRA:
None

Test & Review

Tested on Azure AKS cluster with workload identity enabled.
Run pod with attached k8s service account which is federated to azure managed identity.

Open questions / Follow-ups

We couldn't find example on how to use it with Azure managed identity so we come up with this example.

Review stakeholders

None

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❌ vedrank
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