Update the Docker image versions that are pulled down

[jsf9k]

🗣 Description

This pull request updates the versions of the Docker images that are pulled down to match those being used in cisagov/guacamole-composition.

💭 Motivation and context

If we don't pull the same versions used in cisagov/guacamole-composition then the Docker composition won't work since the Guacamole instance does not have internet access. It also adds a task to pre-create the dbinit directory with the correct permissions.

🧪 Testing

All automated testing passes. I also built a staging AMI with these changes and verified that it functioned as expected.

✅ Pre-approval checklist

• [x] This PR has an informative and human-readable title.
• [x] Changes are limited to a single goal - eschew scope creep!
• [x] All future TODOs are captured in issues, which are referenced in code comments.
• [x] All relevant type-of-change labels have been added.
• [x] I have read the CONTRIBUTING document.
• [x] These code changes follow cisagov code standards.
• [x] Tests have been added and/or modified to cover the changes in this PR.
• [x] All new and existing tests pass.

✅ Pre-merge checklist

• [x] Revert dependencies to default branches.