* BlockId removal: refactor: Backend::justifications
It changes the arguments of `Backend::justifications` method from: `BlockId<Block>` to: `&Block::Hash`
This PR is part of BlockId::Number refactoring analysis (paritytech/substrate#11292)
* trigger CI job
* trigger CI job
* bug fix
* match -> if
Co-authored-by: Adrian Catangiu <adrian@parity.io>
Co-authored-by: Adrian Catangiu <adrian@parity.io>