Allow bypassing automatic setting of fee recipient

[dsimog01]

For protocols like RocketPool or StakeHouse the fee recipient is set automatically. However, StakeHouse needs to perform calls to the eth node running in the Dappnode, so you need to have your clients synced. We could add a checkbox that allows to override this logic (warning the user about the risks of placing a wrong fee recipient), so that they can manually set this fee recipient.