chore(deps): update actions/cache action to v5 (#164)

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>

---

### 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 is behind base branch, 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

---

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View the [repository job
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.github/workflows/pullrequest.yml

@@ -40,7 +40,7 @@ jobs:
 
       - name: Cache Composer packages
         id: root-composer-cache
-        uses: actions/cache@v4
+        uses: actions/cache@v5
         with:
           path: vendor
           key: ${{ runner.os }}-${{ matrix.php-version }}-php-${{ hashFiles('composer.json') }}
@@ -80,7 +80,7 @@ jobs:
 
       - name: Cache Composer packages
         id: behat-composer-cache
-        uses: actions/cache@v4
+        uses: actions/cache@v5
         with:
           path: integration/vendor
           key: ${{ runner.os }}-${{ matrix.php-version }}-php-${{ hashFiles('integration/composer.json') }}