Can't pack into std::span

According to the documentation pack_into should be able to pack_into any byte_container, but the function takes a std:array instead of std::span or equivalent.

bitpacker/include/bitpacker/bitpacker.hpp

Line 822 in c62dbbf

    
           constexpr void pack_into(Fmt /*unused*/, std::array<byte_type, N>& data, const size_type offset, Args&&... args)

thanks for pointing this out! I've been working on a major refactor in the multi-header-2 branch, so I made the fix in a branch off of that. I mainly test with span-lite and this breaks on MSVC right now. I opened up a issue there, and I will see what they say.