fix: inconsistent chain id in rpc backend

[yihuang]

unify backend.EvmChainId and backend.ChainConfig().ChainID

Description

Closes: #XXXX

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[aljo242]

@yihuang we will merge this - but in the future we will require signed commits on this repo

https://docs.github.com/en/authentication/managing-commit-signature-verification/signing-commits

[yihuang]

@yihuang we will merge this - but in the future we will require signed commits on this repo

https://docs.github.com/en/authentication/managing-commit-signature-verification/signing-commits

for this one, it seems tricker than I thought, currently the tests don't all pass, and things are quite confusing to me.

[aljo242]

Looks like they have to do with mock testing. It might just be that the type being passed has changed in your PR?