fix: fix slice init length

[rusttech]

Description

The purpose here should be to initialize a slice with a capacity of len(byzantineValidators) and a length of 0, and then append it later. Instead of initializing the length to len(byzantineValidators) from the beginning, the resulting slice will not meet expectations.

The online demo: https://go.dev/play/p/q1BcVCmvidW

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