[R4R] add block proccess backoff time when validator is not in turn and received in turn block

[yutianwu]

Description

When the network is congested, the possibility of fork blocks is higher. Sometimes it's because validators not in turn propagate the same height block. The validators not in turn have a backoff time but it may can not process the received in turn block in this duration and propagate the same height block. So we add a mechanism to check if the validator received in turn block and increase the backoff time for the process of the in turn block to finish.

Rationale

To reduce the possibility of fork blocks.

Example

Changes

Notable changes:

• Increase backoff time when validators not in turn processing the in turn block

Preflight checks

• build passed (make build)
• tests passed (make test)
• manual transaction test passed

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Related issues

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[kyrie-yl]

I think add a blank line between each case will be better for code readability.

[yutianwu]

most of the codebase doesn't add a blank line, that should be fine