chore(deps): update actions/checkout action to v4

[renovate[bot]]

This PR contains the following updates:

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

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Release Notes

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)

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[codecov[bot]]

Codecov Report

Merging #27 (f9b3a2d) into main (64c469d) will not change coverage. The diff coverage is n/a.

@@            Coverage Diff            @@
##              main       #27   +/-   ##
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  Coverage   100.00%   100.00%           
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  Files            2         2           
  Lines           38        38           
  Branches         5         5           
=========================================
  Hits            38        38