chore(contracts): make release task support all existing contracts

[clemsos]

Description

This PR enables the release of any contract from the smart-contracts folder into the contracts package with a single hardhat cli task (previously only Unlock and PublicLock were supported).

example here :

cd smart-contracts
yarn hardhat release --contract contracts/utils/UnlockSwapPurchaser.sol

Issues

Fixes #
Refs #

Checklist:

• 1 PR, 1 purpose: my Pull Request applies to a single purpose
• I have commented my code, particularly in hard-to-understand areas
• I have updated the docs to reflect my changes if applicable
• I have added tests (and stories for frontend components) that prove my fix is effective or that my feature works
• I have performed a self-review of my own code
• If my code involves visual changes, I am adding applicable screenshots to this thread

Release Note Draft Snippet

[julien51]

Thanks!