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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Configuration

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[codecov[bot]]

Codecov Report

Merging #56 (675c51a) into main (1a03c1f) will decrease coverage by 0.02%. The diff coverage is n/a.

@@            Coverage Diff             @@
##             main      #56      +/-   ##
==========================================
- Coverage   94.98%   94.97%   -0.02%     
==========================================
  Files           4        4              
  Lines         958      956       -2     
==========================================
- Hits          910      908       -2     
  Misses         48       48              

Flag	Coverage Δ
macos_latest	99.32% <ø> (-0.01%)	:arrow_down:
ubuntu_latest	99.33% <ø> (-0.01%)	:arrow_down:
windows_latest	94.48% <ø> (-0.02%)	:arrow_down:

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see 2 files with indirect coverage changes