Update module github.com/moby/buildkit to v0.12.3

[renovate[bot]]

This PR contains the following updates:

Package	Type	Update	Change
github.com/moby/buildkit	require	patch	v0.12.2 -> v0.12.3

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Release Notes

moby/buildkit (github.com/moby/buildkit)

### [`v0.12.3`](https://togithub.com/moby/buildkit/compare/v0.12.2...v0.12.3) [Compare Source](https://togithub.com/moby/buildkit/compare/v0.12.2...v0.12.3)

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Configuration

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