std::unique_ptr is not supported by jlcxx::stl::apply_stl

[omus]

Attempting to use CxxWrap's std::vector support for std::unique_ptrs fails with compilation errors. For example attempting to compile jlcxx::stl::apply_stl<std::unique_ptr<std::string>>(mod); results in:

bazel-out/darwin_arm64-opt/bin/external/libcxxwrap_julia/_virtual_includes/headers/jlcxx/stl.hpp:108:88: error: object of type 'std::vector<std::unique_ptr<std::string>>::value_type' (aka 'std::unique_ptr<std::string>') cannot be assigned because its copy assignment operator is implicitly deleted
    wrapped.method("cxxsetindex!", [] (WrappedT& v, const T& val, cxxint_t i) { v[i-1] = val; });