run make verify_contracts on CONTRACTS_VERSION in the CI builds

[pirapira]

This issue keeps track of changing the CI so it fails when the Solidity sources and contracts.json do not match in data_CONTRACTS_VERSION.

When data_CONTRACTS_VERSION/contracts.json and data_CONTRACTS_VERSION/sources do not match, the deployment script refuses to deploy data_CONTRACTS_VERSION/contracts.json. This affects the private network deployment.

[Dominik1999]

Find out if there is a use case for using old contracts. We do not see that at the first sight.