GitHub actions and jest

[nicolasbrugneaux]

Inspired by #3 but modernized. Will add a similar test case

Note: Looks like a lot of changes because it's based on the following PR:

• Ethers v6 #13

I will rebase it when it's merged.

[nicolasbrugneaux]

Quick write-up regarding testing:

For most tests, a funded wallet is necessary to deploy a test contract, send a transaction with or without feeCurrencies. I came up with 3 solutions and we need to decide what makes more sense:

• 1 constant account (set-up by @jmrossy) with enough funds for the forseeable future
• 1 new account per CI run (meaning some integration with celotooljs to usethe faucet programmatically)
• a mock environment (such as ganache) but the big caveat is the inability to test celo-key features such as fee-currency.

My best bet would be on solution#1, much easier to setup, but it's obviously less elegant (and may run out of funds, who knows)

[jmrossy]

I agree #1 is fine for now and definitely simplest

[nicolasbrugneaux]

Now that #13 was merged, I'll tackle this on Monday, can I ask you to setup an process.env.MNEMONIC for this repo (or give me permission to add it? I think process.env.ACCOUNT should be refactored to not be needed

[jmrossy]

@nicolasbrugneaux Done. I've created the repo secret (called just MNEMONIC) and given you write perms on this repo :)

[nicolasbrugneaux]

Tests are passing on the celo-org fork: https://github.com/celo-org/celo-ethers-wrapper/actions/runs/6629109115/job/18007671031