feat: Blockscout contract verification

[DanielSchiavini]

What I did

• Implement Blockscout contract verification
• Unfortunately, a bug is causing problems when called with boa.loads

How I did it

• Allow verification on vyper deployer, vyper blueprints and vyper contract
• When https://github.com/vyperlang/titanoboa/pull/294 lands, we can also add verification for VVM contracts.

How to verify it

• tests are included
• see example verified contract

Description for the changelog

• Add contract verification on Blockscout

Cute Animal Picture

[charles-cooper]

i reworked path resolution in https://github.com/vyperlang/titanoboa/pull/308/commits/5ce6bfb3fef2ec060c5ddae7a92eeddb7b7d5541, it works now.

~i made the additional change of essentially ignoring the name= parameter, i'm not really sure if anybody uses it though~

rolled back the contract_name= change in https://github.com/vyperlang/titanoboa/pull/308/commits/572ef3f1f74eaeb336078fc48d7ac536489eda54