nebula-agent doesn't have db_playback command implementation

[wangajing]

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Describe the bug (required)

nebula-agent doesn't have db_playback command implementation. nebula-agent Dockerfile has a dependency on db_playback command: https://github.com/vesoft-inc/nebula-agent/blob/master/Dockerfile#L9, but it's not available in this package, which causes dockerfile build failure. is there any reason that why this file not exist?

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How To Reproduce(required)

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Expected behavior

Additional context

[luckercs]

+1， How to obtain a db_playback when build dockerfile？

@MegaByte875 @dutor @kikimo @codesigner @wey-gu