fix: Allow to inject async functions into async generators

[Zhenay]

When you try to inject asynchronous dependencies into an asynchronous generator like this:

async def some_dep() -> int:
    return 5

@inject
async def some_async_gen(value: Annotated[int, Depends(some_dep)]):
    yield value

you see the error You cannot use async dependency `some_dep` at sync main.

This pull request allows the inject function be used in such context. Still do not work with asynccontextmanager decorator though.

[Lancetnik]

Great job, thank you!