chore(deps): update actions/cache action to v5 (#63)

This PR contains the following updates:

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

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### Release Notes

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

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

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

</details>

---

### 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.

---

 - [ ] <!-- rebase-check -->If you want to rebase/retry this PR, check this box

---

This PR has been generated by [Renovate Bot](https://github.com/renovatebot/renovate).
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Reviewed-on: #63
Reviewed-by: t.behrendt <t.behrendt@noreply.localhost>
Co-authored-by: Renovate Bot <renovate@t00n.de>
Co-committed-by: Renovate Bot <renovate@t00n.de>

.gitea/workflows/cd.yaml

@@ -37,7 +37,7 @@ jobs:
             go.sum
       - name: cache go
         id: cache-go
-        uses: actions/cache@0057852bfaa89a56745cba8c7296529d2fc39830 # v4
+        uses: actions/cache@9255dc7a253b0ccc959486e2bca901246202afeb # v5
         with:
           path: |
             /go_path

.gitea/workflows/ci.yaml

@@ -28,7 +28,7 @@ jobs:
             go.sum
       - name: cache go
         id: cache-go
-        uses: actions/cache@0057852bfaa89a56745cba8c7296529d2fc39830 # v4
+        uses: actions/cache@9255dc7a253b0ccc959486e2bca901246202afeb # v5
         with:
           path: |
             /go_path