Double check and possibly refactor and write tests transaction config

[Muhammad-Altabba]

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Code around https://github.com/web3/web3.js/pull/6663/files#diff-9bad653a804ddf07fda4e536c2eb2f6c2a0243b8b7b23752cc5fc6ccf97578d2R391 needs review. Some fixes where applied at https://github.com/web3/web3.js/pull/6663/. But it seems to need more review, edit and test.