Add node 22 and 23 to test matrix

[GaryWilber]

No description provided.

[milindl]

v8 removed v8::CopyablePersistentTraits from the version of v8 used in node v23, and using Nan::CopyablePersistentTraits doesn't seem to work, it gives a template substitution error for node v18. We're trying to get around it by replacing std::vector<v8::Persistent<v8::Function, Nan::CopyablePersistentTraits<v8::Function> > > callbacks with std::vector<Nan::Callback*> callbacks;.