Unpin requests and bump docker-py

[felddy]

🗣 Description

Unpins requests and bumps docker.

See:

• Pin requests dependency to work around docker-py incompatibility #972

💭 Motivation and context

Docker Python API was updated.
Version 12 of Foundry has been released.

🧪 Testing

Locally and in CI

✅ Pre-approval checklist

• This PR has an informative and human-readable title.
• Changes are limited to a single goal - eschew scope creep!
• All relevant type-of-change labels have been added.
• I have read the CONTRIBUTING document.
• These code changes follow cisagov code standards.
• All relevant repo and/or project documentation has been updated
  to reflect the changes in this PR.
• All new and existing tests pass.