chore(gh-actions-deps): update actions/checkout action to v4.2.1 in dev workflows

[renovate[bot]]

This PR contains the following updates:

Package	Type	Update	Change
actions/checkout	action	patch	v4.2.0 -> v4.2.1

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Release Notes

actions/checkout (actions/checkout)

### [`v4.2.1`](https://redirect.github.com/actions/checkout/blob/HEAD/CHANGELOG.md#v421) [Compare Source](https://redirect.github.com/actions/checkout/compare/v4.2.0...v4.2.1) - Check out other refs/\* by commit if provided, fall back to ref by [@​orhantoy](https://redirect.github.com/orhantoy) in [https://github.com/actions/checkout/pull/1924](https://redirect.github.com/actions/checkout/pull/1924)

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Configuration

📅 Schedule: Branch creation - At any time (no schedule defined), Automerge - At any time (no schedule defined).

🚦 Automerge: Enabled.

♻ Rebasing: Whenever PR is behind base branch, 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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This PR was generated by Mend Renovate. View the repository job log.

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 100.00%. Comparing base (75168a5) to head (36a73ce). Report is 1 commits behind head on main.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #148 +/- ## ========================================= Coverage 100.00% 100.00% ========================================= Files 4 4 Lines 211 211 Branches 26 26 ========================================= Hits 211 211 ```

:umbrella: View full report in Codecov by Sentry.
:loudspeaker: Have feedback on the report? Share it here.

[nfelt14]

Blocked by https://github.com/PyCQA/docformatter/issues/293

[github-actions[bot]]

Test Results (windows)

path	passed	subtotal
tests\test_bump_version_in_files.py	5	5
tests\test_create_unique_testpypi_version.py	7	7
tests\test_find_unreleased_changelog_items.py	6	6
tests\test_update_development_dependencies.py	13	13
TOTAL	31	31

Link to workflow run

[github-actions[bot]]

Test Results (ubuntu)

path	passed	subtotal
tests/test_bump_version_in_files.py	5	5
tests/test_create_unique_testpypi_version.py	7	7
tests/test_find_unreleased_changelog_items.py	6	6
tests/test_update_development_dependencies.py	13	13
TOTAL	31	31

Link to workflow run

[github-actions[bot]]

Test Results (macos)

path	passed	subtotal
tests/test_bump_version_in_files.py	5	5
tests/test_create_unique_testpypi_version.py	7	7
tests/test_find_unreleased_changelog_items.py	6	6
tests/test_update_development_dependencies.py	13	13
TOTAL	31	31

Link to workflow run