Follows up PR #4876 which removed the return on non-nil errors
to always return a non-nil REST response regardless of error.
The checks performed seem benign and the return result is the
same.
This change uses the reverse conditional refactoring method
to gut out nesting and many conditions.
Noticed while hunting through types.ParseABCILogs.
Fixes#8181
* refactor auths broadcast cmd in alignment with #6216
* add TxResponse proto definition, and related refactoring
* re-run make proto-gen, updating staking.pb.go
* cleanup TxResponse tests to handle nil return values
* properly handle nil Tx value in TxResponse's implementation of UnpackInterfaces
Co-authored-by: Federico Kunze <31522760+fedekunze@users.noreply.github.com>
Emmanuel T Odeke
MD Aleem
Marko
Cory
SaReN