Decrease size of docker image for Ewing's module

I've made a change for now, but if we _could_ make this smaller, that'd be swell. I prefer how we were handling permissions.

_Originally posted by @jaclyn-taroni in https://github.com/AlexsLemonade/OpenScPCA-analysis/pull/881#discussion_r1844092348_

It's probably a good idea to make the Ewing image smaller so we don't have to use the bigger runner for the GHA.

Currently, we have two versions of the tumor cell annotation workflow. We are only using one of those moving forward. The workflow that we aren't using includes a conda environment, which we don't really need for the other workflow. So I think we could create a smaller image that doesn't have that conda environment. We should go through the code again and double check that this is a reasonable approach.

The issue does not name specific files or tests. Start by locating the Ewing tumor cell annotation workflows and their Docker image definitions, then compare which dependencies the continuing workflow uses. Done means the unused conda environment is removed where appropriate, permissions remain acceptable, and the active workflow runs with a smaller image without requiring the bigger GitHub Actions runner.

Written by the indexing model from the issue text.