Add missing prod.txt dependencies

[KevinMind]

Fixes: mozilla/addons#9481

Description

We merged a broken docker container that cannot run ./manage.py due to missing dependencies in the container.

Context

by merging our requirements files, we accidentally placed production dependencies in dev.txt

Currently we do not have a solid way to determine if what is in prod.txt satisfies our container's needs.

Testing

You can test this locally by building an image

docker build -t test_yaml --platform linux/amd64 --no-cache .

Then run the container

docker run -d --name test_yaml --platform linux/amd64 -v $(pwd):/data/olympia test_yaml tail -f /dev/null

Now shell in and try runing ./manage.py

docker exec -it test_yaml bash   

python3 ./manage.py

You expect to get a list of available subcommands. If dependencies are missing, you will get an error.

NOTE: This is not foolproof. It only verifies that manage.py doesn't throw, but it could be that any one of the subcommands would throw.. I think.

We will ultimately need to design a way to test that our container can run and apply that test before merging PRs. Otherwise we are totally blind and can break master.