Switch to Hardhat configuration variables instead of using `.env`

[andrejrakic]

Update the project to support Hardhat configuration variables instead of using .env file(s)

[lucasarchangelo]

Hey @andrejrakic, In utils.js, some methods rely on process.env, which will cause errors if we migrate to Hardhat variables. I propose refactoring tasks to create the signer object by calling ethers.getSigners(). This way, we won’t need these environment variables anymore.

[edit]
“I have created a new PR (#15) that addresses all the necessary changes before transitioning from the .env file to Hardhat variables.