Proto: SCORU: zero-tick commitment case

Context

The context is in the issue: #3003 (closed)

In addition to the fix to the initial function in the game repr module, this also adds a check to the refine_stake function to prevent a staker making a zero-tick commitment that changes the state hash. (Such a change could not be refuted because there is no step!)

Manually testing the MR

Checklist

• Document the interface of any function added or modified (see the coding guidelines)
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• Provide automatic testing (see the testing guide).
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