23 - Re-add dependencies lost during switch to poetry

[xkortex]

Fix for #23

Looks like during the switch to poetry, the dependencies six and sortedcontainers were lost as primary dependencies. They still existed in the lockfile as dev dependencies, which is why I think they may have fallen through the cracks.

Tested by doing poetry build in a blank env, pip installing the wheel, and ensuring all the imports work. Also ran CI with act, although CI that missed this bug the first time. Not sure what kind of regression test would catch that.

CI passed for all but python 3.10, not sure what's up with that, but it might just be an artifact of using act.

If this approved and CI passes, feel free to merge immediately for me, this is probably time sensitive.

[shadchin]

packaging must also be returned - https://github.com/dsoftwareinc/fakeredis-py/blob/master/fakeredis/aioredis.py#L2

[cunla]

I tested it - it works without it because packaging is a requirement of redis-py (and redis-py of fakeredis).