Updates the agent os supported versions

[RRashmit]

Proposed changes

Write a clear and concise description that helps reviewers understand the purpose and impact of your changes. Use the
following format:

Problem: Updates the agent os supported versions

Solution:

1. Adds support for Alpine 3.21
2. Removes Alpine Linux 3.17 support
3. Removes SLES 12 support

Testing:

Please focus on (optional): If you any specific areas where you would like reviewers to focus their attention or provide
specific feedback, add them here.

If this PR addresses an issue on GitHub, ensure that you link to it here:

Closes #ISSUE

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• If the change involves potentially sensitive changes¹, I have assessed the possible impact
• If applicable, I have added tests that prove my fix is effective or that my feature works
• I have ensured that existing tests pass after adding my changes
• If applicable, I have updated README.md and CHANGELOG.md

Footnotes

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[github-actions]

✅ All required contributors have signed the F5 CLA for this PR. Thank you!
_{Posted by the CLA Assistant Lite bot.}

[RRashmit]

I have hereby read the F5 CLA and agree to its terms

[github-actions]

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[ADubhlaoich]

Generally LGTM!