## Description 

After a block and its transactions are verified, if Mysticeti fastpath
is enabled, vote on the transactions in
`BlockVerifier::verify_and_vote()` and return rejected transaction
indices. If disabled, just return an empty `Vec` of indices.

## Test plan 

CI

---

## Release notes

Check each box that your changes affect. If none of the boxes relate to
your changes, release notes aren't required.

For each box you select, include information after the relevant heading
that describes the impact of your changes that a user might notice and
any actions they must take to implement updates.

- [ ] Protocol: 
- [ ] Nodes (Validators and Full nodes): 
- [ ] gRPC:
- [ ] JSON-RPC: 
- [ ] GraphQL: 
- [ ] CLI: 
- [ ] Rust SDK: