asyncio.create_task(): Remove obsolete section

[srittau]

Documentation

https://docs.python.org/3/library/asyncio-task.html#asyncio.create_task has a section about an alternative for Python 3.6 and prior. Now that 3.6 has reached end of life, this section is obsolete and hurts conciseness. I propose to remove it.

[srittau]

#92224 doesn't get linked automatically.

[AlexWaygood]

Now fixed — thanks @srittau!