chore(deps): update actions/cache action to v4

[renovate[bot]]

This PR contains the following updates:

Package	Type	Update	Change
actions/cache	action	major	v3 -> v4

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Release Notes

actions/cache (actions/cache)

### [`v4`](https://togithub.com/actions/cache/compare/v3...v4) [Compare Source](https://togithub.com/actions/cache/compare/v3...v4)

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Configuration

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♻ 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

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

Comparison is base (83fe2e0) 56.62% compared to head (9c30855) 56.62%.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #1246 +/- ## ======================================= Coverage 56.62% 56.62% ======================================= Files 103 103 Lines 7020 7020 Branches 515 515 ======================================= Hits 3975 3975 Misses 2531 2531 Partials 514 514 ``` | [Flag](https://app.codecov.io/gh/approvers/OreOreBot2/pull/1246/flags?src=pr&el=flags&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=approvers) | Coverage Δ | | |---|---|---| | [unittests](https://app.codecov.io/gh/approvers/OreOreBot2/pull/1246/flags?src=pr&el=flag&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=approvers) | `56.62% <ø> (ø)` | | Flags with carried forward coverage won't be shown. [Click here](https://docs.codecov.io/docs/carryforward-flags?utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=approvers#carryforward-flags-in-the-pull-request-comment) to find out more.

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