chore(deps): update actions/cache action to v5 (#1377)

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/checks.yml

@@ -27,7 +27,7 @@ jobs:
         shell: bash
 
       - name: Cache dependencies
-        uses: actions/cache@v4
+        uses: actions/cache@v5
         with:
           path: .venv
           key: ${{ runner.os }}-${{ steps.get_python_version.outputs.python_version }}-dependencies-${{ hashFiles('**/pdm.lock') }}
@@ -86,7 +86,7 @@ jobs:
         shell: bash
 
       - name: Cache dependencies
-        uses: actions/cache@v4
+        uses: actions/cache@v5
         with:
           path: .venv
           key: ${{ runner.os }}-${{ steps.get_python_version.outputs.python_version }}-min-dependencies-${{ hashFiles('**/pdm.lock') }}
@@ -168,7 +168,7 @@ jobs:
         id: get_python_version
         run: echo "python_version=$(python --version)" >> $GITHUB_OUTPUT
       - name: Cache Generated Client Dependencies
-        uses: actions/cache@v4
+        uses: actions/cache@v5
         with:
           path: integration-tests/.venv
           key: ${{ runner.os }}-${{ steps.get_python_version.outputs.python_version }}-integration-dependencies-${{ hashFiles('integration-tests/pdm*.lock') }}