Issue:

• [N14] Unused code
  Throughout the codebase, there are instances of unused code. For example:
  • The proposerBondRepaid attribute of the HubPool contract's RootBundle struct is never used.
    Consider removing it.
  • The events in the Arbitrum_Adapter contract are never used. As the relevant state variables
    are immutable, consider setting all relevant values in the constructor and emitting these events
    then. Alternatively, consider adding comments indicating why events are declared but unused.
  • The L2GasLimitSet event in the Optimism_Adapter is never emitted. Consider emitting it in the
    constructor, removing it, or adding a comment indicating why it is declared but not used.
  • The HubPoolChanged event is never used.

Resolution:

• proposerBondRepaid was removed in this PR
• All unused adapter events are removed in this PR