EIP-1559 support

[cgewecke]

HH has open issues about adding this:

• Add option to configure default EIP-1559 values NomicFoundation/hardhat#3418
• Allow custom maxPriorityFeePerGas in hardhat.config.js (@hardhat/ethers) NomicFoundation/hardhat#1866

Also relevant...it is actually possible to set these...workaround from:

• Add option to adjust EIP-1559 gas fields in the Hardhat Network config NomicFoundation/hardhat#3298

const FEE_DATA = {
    maxFeePerGas:         ethers.utils.parseUnits('100', 'gwei'),
    maxPriorityFeePerGas: ethers.utils.parseUnits('5',   'gwei'),
    baseFeePerGas : ethers.utils.parseUnits('20',   'gwei'),
};

  // Wrap the provider so we can override fee data.
  const provider = new ethers.providers.FallbackProvider([ethers.provider], 1);
  provider.getFeeData = async () => FEE_DATA;

  const signer = new ethers.Wallet(process.env.PRI_KEY1, provider);
  const StakingRewards = await ethers.getContractFactory("StakingRewards",signer);`