replace httpc with gun

[SimonUnge]

Proposed Changes

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Types of Changes

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• Bug fix (non-breaking change which fixes issue #NNNN)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause an observable behavior change in existing systems)
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• Cosmetic change (whitespace, formatting, etc)
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Checklist

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• I have read the CONTRIBUTING.md document
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• I have added tests that prove my fix is effective or that my feature works
• All tests pass locally with my changes
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• If relevant, I have added this change to the first version(s) in release-notes that I expect to introduce it

Further Comments

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