* contracts-bedrock: remove LegacyERC20ETH contract

The `LegacyERC20ETH` is no longer used as part of the genesis
generation. Is a contract that only lives on OP Mainnet and is
no longer used since the bedrock upgrade. It is completely deprecated
at this point and there is no real reason to keep around its source
code since it isn't placed into modern genesis states. It has no
usage anymore and keeping it around only bloats the lines of code
in the contracts, increases the build time and increases the test
time.

* contracts-bedrock: fix build

* op-bindings: remove LegacyERC20ETH

No longer used

* contracts-bedrock: update gas snapshot