eth-bytecode-db bug: grpc connection

[sevenzing]

we noted that eth-bytecode-db doesnt response on simple

curl 'https://eth-bytecode-db.services.blockscout.com/api/v2/verifier/solidity/versions'

also, service doesn't log anything. After a restart, error didnt go away. After smart-contract-verifier restart error resolved.

My assumption is that grpc connection between eth-bytecode-db and verifier is lost and couldn't be fixed for some reason. My suggestion is to add logging and investigate the problem. Or move to http connections between services

[rimrakhimov]

We've improved logging capabilities for eth-bytecode-db and smart-contract-verifier services, so that now it would be easier to fix the problem if that occurs.

Besides that we are planning to move to the HTTP client for the eth-bytecode-db to send requests to the verifier