[improve][broker][PIP-149]make getPublishRate getDispatchRate setDispatchRate method async in Namespaces

[HQebupt]

Motivation

Fixed #15946 due to It miss v1/Namespaces.java.

See PIP #14365 and change tracker #15043.
Make removePublishRate / getPublishRate / getDispatchRate / setDispatchRate / deleteDispatchRate methods in NamespacesBase to pure async.

Verifying this change

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Does this pull request potentially affect one of the following parts:

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• Dependencies (does it add or upgrade a dependency): (no)
• The public API: (no)
• The schema: (no)
• The default values of configurations: (no)
• The wire protocol: (no)
• The rest endpoints: (no)
• The admin cli options: (no)
• Anything that affects deployment: (no)

Documentation

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[HQebupt]

/pulsarbot run-failure-checks

[Technoboy-]

V1 is no longer recommended to fix

[HQebupt]

V1 is no longer recommended to fix

Good.