feat: add workflow-dispatch trigger to build workflow

[b1rger]

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• Change B

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Related issues and PRs
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Resolves issue:

• Cluster-2 not in allowed hosts per project #11
• #42

Supersedes PR:

• fix: make gunicorn verbose #13

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• My changes don't generate new warnings or errors
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• I have commented my code with Docstrings and code comments, particularly complex, unusual or hard-to-read code
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• I have added new unit tests or updated existing ones to demonstrate my changes works