remove async task does not remove the proper task

[leruitga-ss]

Hi there!

I've ran into an issue when trying to remove async tasks from the queue. When searching the index in the queue for the task to remove, it always leads to a negative index due to the fact that the enqueue function does not return the same object as it stores. (probably should push the task object in line 63).

That being said, it would also be nice to have a security check before splicing the queue array.

Thanks for your work! Have a nice day, Gauthier