Update klutchell/unbound Docker tag to v1.20.0

[chemical-soup]

This PR contains the following updates:

Package	Type	Update	Change
klutchell/unbound	final	minor	v1.19.3 -> v1.20.0

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Release Notes

klutchell/unbound-docker (klutchell/unbound)

### [`v1.20.0`](https://togithub.com/klutchell/unbound-docker/compare/v1.20.0...v1.20.0) [Compare Source](https://togithub.com/klutchell/unbound-docker/compare/v1.20.0...v1.20.0) ### [`v1.20.0`](https://togithub.com/klutchell/unbound-docker/compare/v1.19.3...v1.20.0) [Compare Source](https://togithub.com/klutchell/unbound-docker/compare/v1.19.3...v1.20.0)

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Configuration

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