chore(deps): update actions/checkout action to v4.2.1

[renovate]

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

Compare Source

• Check out other refs/* by commit if provided, fall back to ref by @​orhantoy in https://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: Disabled by config. Please merge this manually once you are satisfied.

♻ 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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This PR was generated by Mend Renovate. View the repository job log.

[github-actions]

SpotBugs

Category	Base	New
Bad practice	35	35
Correctness	34	34
Dodgy code	26	26
Internationalization	6	6
Malicious code vulnerability	49	49
Multithreaded correctness	3	3
Performance	8	8
Total	161	161

[nextcloud-android-bot]

master-IT test failed: https://www.kaminsky.me/nc-dev/android-library-integrationTests/3397-IT-master-10-58/debug/