[Docker-in-Docker] - Update docker-compose to the latest version

[Kaniska244]

Summary

Updates the Docker-in-Docker dev container feature to make latest the default Docker Compose version.

This change adds latest as a supported value for the dockerDashComposeVersion option, changes the default from v2 to latest, and updates the feature metadata, install script defaults, README documentation, and test scenarios accordingly.

Changes

• Bumps the docker-in-docker feature version from 3.0.1 to 3.1.0.
• Adds latest to the supported dockerDashComposeVersion enum values.
• Changes the default dockerDashComposeVersion from v2 to latest.
• Updates the option description in both:
  • src/docker-in-docker/devcontainer-feature.json
  • src/docker-in-docker/README.md
• Updates install.sh so the default Docker Compose version is latest.
• Adds test coverage for dockerDashComposeVersion: "latest" with:
  • Moby enabled
  • Moby disabled

Updated Behavior

Previously, when dockerDashComposeVersion was not explicitly set, the feature defaulted to:

"dockerDashComposeVersion": "v2"

After this change, the feature defaults to:

"dockerDashComposeVersion": "latest"

The supported values are now:

none
latest
v1
v2

Testing

Added new Docker-in-Docker test scenarios for Docker Compose latest:

• docker_compose_latest_moby
• docker_compose_latest_no_moby

The new test verifies that:

• docker compose version returns a valid semantic version.
• docker-compose --version returns a valid semantic version.
• Docker Compose is installed as /usr/local/bin/docker-compose.

Files Changed

• src/docker-in-docker/devcontainer-feature.json
• src/docker-in-docker/install.sh
• src/docker-in-docker/README.md
• test/docker-in-docker/scenarios.json
• test/docker-in-docker/docker_compose_latest_no_moby.sh
• test/docker-in-docker/docker_compose_latest_moby.sh