EIP7251: Fix partial withdrawal balance update

[hangleang]

reference spec change: ethereum/consensus-specs#3979

[Tumas]

Hi, this is already covered in devnet5 branch. Devnet5 branch contains latest changes for Pectra: https://github.com/grandinetech/grandine/tree/devnet5

We won't be merging it to develop until Mekong / devnet4 is live as it contains breaking changes. If you find any changes that are missing, feel free create merge requests for that branch.

I've also incorporated changes from #62 into it.

[hangleang]

Ahh, I just saw that branch for devnet-5, it already covered this pr.

I will check the rest of my recent PRs. if there is any missing in that branch, I will change base to that. if not, I will close in favor of exist code.

And thank for put the #62 into that branch as well 🙏