.github: Update actions/checkout action to v6

[ata-no-one]

This PR contains the following updates:

Package	Type	Update	Change
actions/checkout	action	major	v5 -> v6

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⚠️ Warning

Some dependencies could not be looked up. Check the warning logs for more information.

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Release Notes

actions/checkout (actions/checkout)

v6

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

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This PR has been generated by Renovate Bot.

[ata-no-one]

Edited/Blocked Notification

Renovate will not automatically rebase this PR, because it does not recognize the last commit author and assumes somebody else may have edited the PR.

You can manually request rebase by checking the rebase/retry box above.

⚠️ Warning: custom changes will be lost.

[ata-no-one]

Renovate Ignore Notification

Because you closed this PR without merging, Renovate will ignore this update. You will not get PRs for any future 6.x releases. But if you manually upgrade to 6.x then Renovate will re-enable minor and patch updates automatically.

If you accidentally closed this PR, or if you changed your mind: rename this PR to get a fresh replacement PR.