chore(deps): update actions/checkout action to v5

[renovate]

This PR contains the following updates:

Package	Type	Update	Change
actions/checkout	action	major	v4 -> v5

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Release Notes

actions/checkout (actions/checkout)

v5

Compare Source

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

[mergify]

🧪 CI Insights

Here's what we observed from your CI run for 997912c.

❌ Failed Jobs

Pipeline	Job	Health on base branch	Retries	🔍 CI Insights	📄 Logs
Build and test flake outputs	Discover Hosts		0	View	View
	Discover Users		0	View	View
Build packages	Discover Packages		0	View	View

✅ Passed Jobs With Interesting Signals

Pipeline	Job	Signal	Health on base branch	Retries	🔍 CI Insights	📄 Logs
Build and test flake outputs	test (flake check --no-pure-eval --allow-import-from-derivation, x86_64-linux)	Base branch is broken, but the job passed. Looks like this might be a real fix 💪		0	View	View