feat: update hardhat toolbox for ethers v6

[sebastiendan]

Description

This PR updates ethers and hardhat-toolbox so that the global stack can upgrade ethers to v6.

Fixes TOO-397

PR Checklist:

• I have performed a self-review of my code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• I have added or updated tests that comprehensively prove my change is effective or that my feature works

[sebastiendan]

@dvdplm That's an early draft, many other updates are incoming