[Fidelity] Remove redundant fields from fidelity bond #655
Description
Since we transitioned from a certificate based fidelity bond to embedding tor addresses on the blockchain, there are a bunch of redundant fields and can be removed such as cert_expiry. In fact, we can get rid of the entire FidelityProof and its constituent fields cert_hash and cert_sig.
This will require identifying the redundant fields and logic in the Fidelity creation and verification flow, removing the redundant parts and replacing with simpler, up-to-date logic.