[MSVC][std:c++latest] Trojan build failed due to error C2666: 'boost::date_time::base_time<boost::posix_time::ptime,boost::posix_time::posix_time_system>::operator ==': overloaded functions have similar conversions

[fangzhouxia]

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Trojan Version
We use commit is 3e7bb9a

Describe the bug
After the MSVC team implented P2468R2 The Equality Operator You Are Looking For, we got a compiler error with /std:c++latest like below, the error is due to the operator== https://github.com/boostorg/date_time/blob/develop/include/boost/date_time/time.hpp#L137. In order to fix this the 'ref' log_entry::ref class need to add a corresponding 'operator!=' like so:

bool operator!=(const time_type& rhs) const
    {
      return time_system::is_equal(time_,rhs.time_);
    }

Could you please look this issue? Thanks.
Note: this issue will be reproduced on next release version of VS(17.6 or later).

To Reproduce
Steps to reproduce the behavior:

1. open VS2019 x64 tools command
2. git clone https://github.com/trojan-gfw/trojan F:\gitP\trojan-gfw\trojan
3. set CL= /std:c++latest
4. cd F:\gitP\trojan-gfw\trojan &mkdir build_amd64 &cd F:\gitP\trojan-gfw\trojan\build_amd64
5. cmake -G "Visual Studio 16 2019" -A x64 -DCMAKE_SYSTEM_VERSION=10.0.18362.0 -DOPENSSL_ROOT_DIR=F:\tools\OpenSSL\64 -DBOOST_ROOT=F:\tools\boost_1_67_0\x64 -DCMAKE_BUILD_TYPE=Release -DENABLE_MYSQL=OFF -DBoost_USE_STATIC_LIBS=ON ..
6. msbuild /m /p:Platform=x64 /p:Configuration=Release trojan.sln /t:Rebuild

Expected behavior
Build successfully.
Logs
F:\tools\boost_1_67_0\x64\boost/asio/ssl/detail/io.hpp(152): error C2666: 'boost::date_time::base_timeboost::posix_time::ptime,boost::posix_time::posix_time_system::operator ==': overloaded functions have similar conversions
F:\tools\boost_1_67_0\x64\boost/date_time/time.hpp(126): note: could be 'bool boost::date_time::base_timeboost::posix_time::ptime,boost::posix_time::posix_time_system::operator ==(const boost::posix_time::ptime &) const'
F:\tools\boost_1_67_0\x64\boost/date_time/time.hpp(126): note: or 'bool boost::date_time::base_timeboost::posix_time::ptime,boost::posix_time::posix_time_system::operator ==(const boost::posix_time::ptime &) const' [synthesized expression 'y == x']
F:\tools\boost_1_67_0\x64\boost/bind/arg.hpp(48): note: or 'bool boost::operator ==(const boost::arg &,const boost::arg &)'
F:\tools\boost_1_67_0\x64\boost/asio/ssl/detail/io.hpp(152): note: 'bool boost::operator ==(const boost::arg &,const boost::arg &)': could not deduce template argument for 'const boost::arg &' from 'boost::posix_time::ptime'
F:\tools\boost_1_67_0\x64\boost/optional/detail/optional_relops.hpp(165): note: or 'bool boost::operator ==(boost::none_t,const boost::optional &) noexcept'

Environment
VS version: VS2019(16.11.20)
Operating system: windows server 2019
Additional context
build (1).log