Unable to execute transaction using ethers provider on Alfajores network

[kosecki123]

Setup

Deploy the contract on Alfajores (you need an account with CELO token)

PK=<private key> yarn hardhat deploy --network alfajores

You should see standard output from the hardhat deployment:

deploying "ERC20" (tx: 0x4cde040adec11a2a8f37ce9eeb02db4ba24604e7c70ce19d99b42fb36a7230ba)...: deployed at 0x5D05e448aC254ec032d87ec0CCDff238592508Ea with 415896 gas

Test 1

PK=<paste here the private key from listing above> CONTRACT=<paste here the address of deployed contract> WEB3_PROVIDER=https://alfajores-forno.celo-testnet.org node scripts/transfer_ethers.js

The output should have an error containing:

reason: 'invalid BigNumber value',
  code: 'INVALID_ARGUMENT',
  argument: 'value',
  value: undefined,
  checkKey: 'gasLimit',
  checkValue: undefined

Now, executing same transaction but using vanilla CeloProvider as implemented ends without any issues.

This is an opposite to what was reported in #1 and makes the working with both local and alfajores impossible since it's either vanilla provider or celoprovider that works.