remove ethers dependency on system txs

[eyusufatik]

Description

Removes dependency on ethers in system transactions module. This is helpful for batch proving

This is a part of #329

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 81.4%. Comparing base (ecc847c) to head (77e9da8).
Report is 1 commits behind head on nightly.

Additional details and impacted files

Files	Coverage Δ
crates/evm/src/evm/system_contracts/mod.rs	100.0% <100.0%> (ø)
crates/evm/src/evm/system_events.rs	98.0% <100.0%> (-0.2%)	⬇️

... and 2 files with indirect coverage changes