Install the latest version of the Guacamole Docker composition

[jsf9k]

🗣 Description

This pull request modifies the Ansible role to use the latest version of the Guacamole Docker composition.

💭 Motivation and context

The latest version of the Docker composition uses the latest version of the cisagov/guacscanner Docker image. This newer Docker image should function identically to the old one, but with potentially better performance. See the following PRs for more details:

• cisagov/guacscanner#68
• cisagov/guacscanner#94
• cisagov/guacscanner#96
• cisagov/guacscanner-docker#20
• cisagov/guacscanner-docker#21
• cisagov/guacamole-composition#52

🧪 Testing

All automated testing passes.

✅ 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 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.