Ethers v6 upgrade

[harbu]

Summary

Please provide a summary of the changes and a motivation if applicable.

Changes

Provide a bullet list of individual changes. Leave this section out if change set is small and obvious from summary.

Limitations and future improvements

Provide a bullet list or description of known omissions or limitations of the solution and/or any ideas for future improvement. Leave section ouf if not applicable.

Checklist before requesting a review

• [ ] Is this a breaking change? If it is, be clear in summary.
• [ ] Read through code myself one more time.
• [ ] Make sure any and all TODO comments left behind are meant to be left in.
• [ ] Has reasonable passing test coverage?
• [ ] Updated changelog if applicable.
• [ ] Updated documentation if applicable.