[DNM] capture: make capture info register & unregister atomic.

[3AceShowHand]

What problem does this PR solve?

close #2388

What is changed and how it works?

• add an atomic variable to control the register and unregister capture info into etcd.
• fix some lint and typo when wql

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• Manual test (add detailed scripts or steps below)

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[3AceShowHand]

close, pr should based on v4.0