[NFCI][SYCL][Graph] Cleanup after enable_shared_from_this for queue_impl

[aelovikov-intel]

foo(const std::shared_ptr<queue_impl> &) doesn't provide any information about possible nullptr arguments. It could provide information about possibility of creating a copy if used sparsely, but when entire codebase passes all objects like this it's meaningless too.

Instead of that, the WIP refactoring across the entire codebase is to pass by raw ptr/ref (depending on the possibility of nullptr value) and extending lifetimes with explicit shared_from_this().

This PR is limited to graph_impl.hpp interfaces accepting queue_impl, clean up after #18715.

[aelovikov-intel]

I had to move this and the ones below into the graph_impl.cpp because queue_impl is incomplete at this point. queue_impl.hpp/graph_impl.hpp include each other (which is totally wrong but not the subject of this PR) and untangling that would be a task that I'm not willing to take on, at least not now.

Another alternative would be to make these templates:

template <typename QueueImplTy = queue_impl>
void foo(QueueImplTy &Q)

to make weak_from_this() template-type-dependent and delay the requirement for a complete type until foo is instantiated (vs defined as of now).

Accepting std::weak_ptr<queue_impl> would also work (and some pre-existing methods do just that already) but I find it lacking in expressiveness - it doesn't communicate expectations about nullptr possibility of if the argument can be in already expired state.