Update module github.com/alecthomas/kong to v0.2.18

[renovate[bot]]

This PR contains the following updates:

Package	Type	Update	Change
github.com/alecthomas/kong	require	patch	v0.2.17 -> v0.2.18

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Release Notes

alecthomas/kong

### [`v0.2.18`](https://togithub.com/alecthomas/kong/compare/v0.2.17...v0.2.18) [Compare Source](https://togithub.com/alecthomas/kong/compare/v0.2.17...v0.2.18)

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Configuration

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