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 #25 (3d0dcbf) into master (58c9c2f) will not change coverage. The diff coverage is n/a.

@@           Coverage Diff           @@
##           master      #25   +/-   ##
=======================================
  Coverage   98.92%   98.92%           
=======================================
  Files          23       23           
  Lines         745      745           
  Branches       42       42           
=======================================
  Hits          737      737           
  Misses          8        8           

Flag	Coverage Δ
integration	98.92% <ø> (ø)
unit	97.43% <ø> (ø)

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