Support for blueprint contracts

[rimrakhimov]

Add support for blueprint contracts (EIP-5202).

The support from eth-bytecode-db and smart-contract-verifier was added in blockscout/blockscout-rs#851. It resulted in a new is_blueprint key inside the source structure. From the backend side we need the following:

1. Add a new is_blueprint boolean column into smart_contracts table
2. Set smart_contracts.is_blueprint in accordance with a new source.is_blueprint verifier response
3. Add is_blueprint value into SmartContract view returned via api v2