Update dependency webpack-merge to v6

[renovate[bot]]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
webpack-merge	5.10.0 -> 6.0.1

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Release Notes

survivejs/webpack-merge (webpack-merge)

### [`v6.0.1`](https://togithub.com/survivejs/webpack-merge/blob/HEAD/CHANGELOG.md#601--2024-07-02) [Compare Source](https://togithub.com/survivejs/webpack-merge/compare/v6.0.0...v6.0.1) - Fix - Restore usage of `clone-deep` as there was a corner case where `structuredClone` did not work as expected. [#​214](https://togithub.com/survivejs/webpack-merge/issues/214) ### [`v6.0.0`](https://togithub.com/survivejs/webpack-merge/blob/HEAD/CHANGELOG.md#600--xxxx-xx-xx) [Compare Source](https://togithub.com/survivejs/webpack-merge/compare/v5.10.0...v6.0.0) - Chore - Update internal dependencies. As a result, the package needs at least Node 18 to run. - Chore - Use `structuredClone` over `clone-deep` dependency since it is included to Node 18 or above. [#​214](https://togithub.com/survivejs/webpack-merge/issues/214)

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Configuration

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