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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Configuration

📅 Schedule: Branch creation - "every weekend" in timezone Etc/UTC, Automerge - "every weekend" in timezone Etc/UTC.

🚦 Automerge: Enabled.

♻ Rebasing: Whenever PR becomes conflicted, or you tick the rebase/retry checkbox.

🔕 Ignore: Close this PR and you won't be reminded about this update again.

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

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[codecov[bot]]

Codecov Report

Merging #100 (e3eefc4) into main (9d33a2e) will not change coverage. The diff coverage is n/a.

@@           Coverage Diff           @@
##             main     #100   +/-   ##
=======================================
  Coverage   90.17%   90.17%           
=======================================
  Files          13       13           
  Lines         692      692           
  Branches      141      141           
=======================================
  Hits          624      624           
  Misses         50       50           
  Partials       18       18