errors building EVM contract with 4.0

[spoonincode]

I can't tell if this is something buggy in cdt or EVM contract. It's at least a regression for a contract that compiles fine in cdt 3.1

https://github.com/eosnetworkfoundation/eos-evm/actions/runs/4878774094/jobs/8704718768

[stephen-diesel]

Assumed to potentially be failing due to recent boost changes

[dimas1185]

this is better to fix on evm side:

here is the problem:
evm has

DataStream& operator<<(DataStream& ds, const std::basic_string<uint8_t>& bs)

defined as it wasn't defined in cdt

and datastream was recently enhanced with this one:

datastream<Stream>& operator << ( datastream<Stream>& ds, const std::basic_string<T>& s )

this causes error: use of overloaded operator '<<' is ambiguous.
Solution is to remove aforementioned code from evm_contract.hpp

[spoonincode]

Thanks for looking in to it; I went ahead and made VaultaFoundation/evm-contract#533 to track it over there