HAL-04: Add warning to HolographOperator for setUtilityToken

[alexanderattar]

Description

This simply provides a warning for an issue identified by Halborn. We would like to keep the function for now although it should never need to be called outside of a dev environment. In the super unlikely reason this would ever need to be called on production, the warning provides instructions for clearing the _bondedAmounts mapping during the migration.

The HolographOperator contract implements the function setUtilityToken():

/**
 * @notice Update the Holograph Utility Token address
 * @param utilityToken address of the Holograph Utility Token smart contract to use
 */
function setUtilityToken(address utilityToken) external onlyAdmin {
  assembly {
    sstore(_utilityTokenSlot, utilityToken)
  }
}

However, when a new utility token is set by an admin, the _bondedAmounts mapping is not reset to 0, breaking all the slashing infrastructure.

Recommendation
When a new utility token is set by an admin all the _bondedAmounts keys should be reset to 0. On the other hand, as the previous suggestion is nearly impossible to implement without very high gas costs, consinder simply removing the setUtilityToken() function.

Checklist before requesting a review

• I have performed a self-review of my code
• Code styles have been enforced
• All Foundry tests are passing

[sogoiii]

👍