Update actions/cache action to v4 (#286)

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This PR contains the following updates:

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

---

### Release Notes

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

### [`v4`](https://togithub.com/actions/cache/compare/v3...v4)

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

</details>

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.github/workflows/ci.yml

@@ -29,7 +29,7 @@ jobs:
 
       - name: Load cached Poetry installation
         id: cached-poetry
-        uses: actions/cache@v3
+        uses: actions/cache@v4
         with:
           path: ~/.local
           key: poetry-${{ runner.os }}-${{ env.POETRY_VERSION  }}-${{ steps.setup-python.outputs.python-version }}
@@ -48,7 +48,7 @@ jobs:
 
       - name: Load cached venv
         id: cached-poetry-dependencies
-        uses: actions/cache@v3
+        uses: actions/cache@v4
         with:
           path: .venv
           key: venv-${{ runner.os }}-${{ steps.setup-python.outputs.python-version }}-${{ hashFiles('**/poetry.lock') }}

.github/workflows/publish.yml

@@ -30,7 +30,7 @@ jobs:
 
       - name: Load cached Poetry installation
         id: cached-poetry
-        uses: actions/cache@v3
+        uses: actions/cache@v4
         with:
           path: ~/.local
           key: poetry-${{ runner.os }}-${{ env.POETRY_VERSION  }}-${{ steps.setup-python.outputs.python-version }}
@@ -49,7 +49,7 @@ jobs:
 
       - name: Load cached venv
         id: cached-poetry-dependencies
-        uses: actions/cache@v3
+        uses: actions/cache@v4
         with:
           path: .venv
           key: venv-${{ runner.os }}-${{ steps.setup-python.outputs.python-version }}-${{ hashFiles('**/poetry.lock') }}