Update actions/cache action to v4 (#290)

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This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| [actions/cache](https://github.com/actions/cache) | action | major |
`v3.3.3` -> `v4.0.0` |

---

### Release Notes

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

### [`v4.0.0`](https://github.com/actions/cache/releases/tag/v4.0.0)

[Compare
Source](https://github.com/actions/cache/compare/v3.3.3...v4.0.0)

##### What's Changed

- Update action to node20 by
[@&#8203;takost](https://github.com/takost) in
[https://github.com/actions/cache/pull/1284](https://github.com/actions/cache/pull/1284)
- feat: save-always flag by [@&#8203;to-s](https://github.com/to-s) in
[https://github.com/actions/cache/pull/1242](https://github.com/actions/cache/pull/1242)

##### New Contributors

- [@&#8203;takost](https://github.com/takost) made their first
contribution in
[https://github.com/actions/cache/pull/1284](https://github.com/actions/cache/pull/1284)
- [@&#8203;to-s](https://github.com/to-s) made their first
contribution in
[https://github.com/actions/cache/pull/1242](https://github.com/actions/cache/pull/1242)

**Full Changelog**: actions/cache@v3...v4.0.0

</details>

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.github/workflows/main.yml

@@ -47,7 +47,7 @@ jobs:
           pip3 install --disable-pip-version-check --progress-bar off 'poetry'
 
       - name: Cache dependencies
-        uses: actions/cache@e12d46a63a90f2fae62d114769bbf2a179198b5c # v3.3.3
+        uses: actions/cache@13aacd865c20de90d75de3b17ebe84f7a17d57d2 # v4.0.0
         with:
           path: ~/.cache/pip
           key: ${{ runner.os }}-pip-${{ hashFiles('**/pyproject.toml') }}