Update lessons 2, 3, 4, 5 with new Hardhat, ethers.js versions. And now OZ is using 0.8.20.....

**Hardhat and ethers.js get significant upgrades with breaking changes for our lessons**

That means we need to either rerun the lessons to get the updated code output and update the lessons, or just manually update the code that will now break our present code e.g. `.deployed()` and `.utils()` have been changed or retired.

There is also a mention about **Network helpers re-export**. I'm not 100% sure what that means (without researching it more):
`import helpers from "@nomicfoundation/hardhat-toolbox/network-helpers";`

Check the link for all the details: https://github.com/NomicFoundation/hardhat/releases/tag/%40nomicfoundation%2Fhardhat-toolbox%403.0.0

- [x] fixed *Build a Basic NFT* lesson
- [x] fixed *TierNFT* lesson
- [ ] checked need for changes and/or fixed **Write Automated Test for Your Smart Contracts** lesson
- [ ] checked need for changes and/or fixed **Connecting to a Front End** lesson

Can we find out about these types of things: https://github.com/NomicFoundation/hardhat/releases/tag/%40nomicfoundation%2Fhardhat-toolbox%403.0.0 in a more predictable way? e.g. I came across a bug, and searched, and then had some luck and found this link. Could we get an alert from somewhere? e.g. to the repo, or is it an idea to have a **Breaking changes** channel in the DAO?