Description of changes

• Detect OS before run the self-termination command
• If the OS is ubuntu2404, run systemctl poweroff --force instead of shutdown -h now
• Added test cases to cover the changes

Tests

• I created a AL2 and Ubuntu2404 cluster to manually test. Test done. Works as expected.

Checklist

• Make sure you are pointing to the right branch.
• If you're creating a patch for a branch other than develop add the branch name as prefix in the PR title (e.g. [release-3.6]).
• Check all commits' messages are clear, describing what and why vs how.
• Make sure to have added unit tests or integration tests to cover the new/modified code.
• Check if documentation is impacted by this change.

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