[signer] event parity should apply to all incoming signer messages

[jferrant]

Currently event parity is only applied to a block proposal. It should be applied to both SignerEvent::BlockValidationResponse(_) and Some(SignerEvent::MinerMessages(..)). The lack of proper reward cycle checks caused the chain to stall. See #5612

This will require changes to both the node and the signer.

As part of this ticket, remove the parity check within the hotfix handle_block_validate_* fns as it should be done in the outer call (also prevents double incrementing metrics when they shouldn't be)

[jferrant]

Related to #5662

[aldur]

Closing this since it might be fixed/not needed anymore. We can re-open if we need it.

[blockstack-devops]

This issue has been automatically locked since there has not been any recent activity after it was closed. Please open a new issue for related bugs.