Update actions/checkout action to v4

[renovate[bot]]

This PR contains the following updates:

Package	Type	Update	Change
actions/checkout	action	major	v3.6.0 -> v4.0.0

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Release Notes

actions/checkout (actions/checkout)

### [`v4.0.0`](https://togithub.com/actions/checkout/blob/HEAD/CHANGELOG.md#v400) [Compare Source](https://togithub.com/actions/checkout/compare/v3.6.0...v4.0.0) - [Support fetching without the --progress option](https://togithub.com/actions/checkout/pull/1067) - [Update to node20](https://togithub.com/actions/checkout/pull/1436)

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Configuration

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• [ ] If you want to rebase/retry this PR, check this box

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[codecov[bot]]

Codecov Report

Merging #20 (aa4426c) into main (2435ad8) will not change coverage. The diff coverage is n/a.

@@           Coverage Diff           @@
##             main      #20   +/-   ##
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  Coverage   68.42%   68.42%           
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  Files           2        2           
  Lines          38       38           
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  Hits           26       26           
  Misses         12       12