force functions and connector using v3 api admin client

[freeznet]

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Motivation

For functions and connectors user, they will need to set api_version to v3 when managing pulsar functions and connectors. But once the api_version set to v3, there is no way to manage other pulsar resources like tenants, because those resources are using v2 apis.
This PR forces the functions and connectors using v3 API, at the same time, it will fall-back to v2 if accessing other resources apis. To make the pulsar provider works for all admin apis at the same provider instance.

Modifications

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This change is a trivial rework / code cleanup without any test coverage.

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• Added integration tests for end-to-end deployment with large payloads (10MB)
• Extended integration test for recovery after broker failure

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[github-actions]

@freeznet:Thanks for your contribution. For this PR, do we need to update docs?
(The PR template contains info about doc, which helps others know more about the changes. Can you provide doc-related info in this and future PR descriptions? Thanks)

[github-actions]

@freeznet:Thanks for providing doc info!