ci: update github actions dependencies to v4

[renovate[bot]]

This PR contains the following updates:

Package	Type	Update	Change
actions/cache	action	major	v3 -> v4
actions/checkout	action	major	v3 -> v4
actions/setup-node	action	major	v3 -> v4
actions/upload-artifact	action	major	v3 -> v4
codecov/codecov-action	action	major	v3 -> v4
peaceiris/actions-gh-pages	action	major	v3 -> v4

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Release Notes

actions/cache (actions/cache)

### [`v4`](https://togithub.com/actions/cache/compare/v3...v4) [Compare Source](https://togithub.com/actions/cache/compare/v3...v4)

actions/checkout (actions/checkout)

### [`v4`](https://togithub.com/actions/checkout/blob/HEAD/CHANGELOG.md#v400) [Compare Source](https://togithub.com/actions/checkout/compare/v3...v4) - [Support fetching without the --progress option](https://togithub.com/actions/checkout/pull/1067) - [Update to node20](https://togithub.com/actions/checkout/pull/1436)

actions/setup-node (actions/setup-node)

### [`v4`](https://togithub.com/actions/setup-node/compare/v3...v4) [Compare Source](https://togithub.com/actions/setup-node/compare/v3...v4)

actions/upload-artifact (actions/upload-artifact)

### [`v4`](https://togithub.com/actions/upload-artifact/compare/v3...v4) [Compare Source](https://togithub.com/actions/upload-artifact/compare/v3...v4)

codecov/codecov-action (codecov/codecov-action)

### [`v4`](https://togithub.com/codecov/codecov-action/compare/v3...v4) [Compare Source](https://togithub.com/codecov/codecov-action/compare/v3...v4)

peaceiris/actions-gh-pages (peaceiris/actions-gh-pages)

### [`v4`](https://togithub.com/peaceiris/actions-gh-pages/compare/v3...v4) [Compare Source](https://togithub.com/peaceiris/actions-gh-pages/compare/v3...v4)

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