chore(deps): update actions/cache action to v5 (#614)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| [actions/cache](https://redirect.github.com/actions/cache) | action |
major | `v4` -> `v5` |

---

### Release Notes

<details>
<summary>actions/cache (actions/cache)</summary>

### [`v5`](https://redirect.github.com/actions/cache/compare/v4...v5)

[Compare
Source](https://redirect.github.com/actions/cache/compare/v4...v5)

</details>

---

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are satisfied.

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rebase/retry checkbox.

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---

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this box

---

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.github/workflows/links.yml

@@ -13,7 +13,7 @@ jobs:
     steps:
       - uses: actions/checkout@v6
 
-      - uses: actions/cache@v4
+      - uses: actions/cache@v5
         with:
           path: .lycheecache
           key: cache-lychee-${{ github.sha }}