chore(deps): update actions/setup-python action to v5.6.0 (#801)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
|
[actions/setup-python](https://redirect.github.com/actions/setup-python)
| action | minor | `v5.5.0` -> `v5.6.0` |

---

### Release Notes

<details>
<summary>actions/setup-python (actions/setup-python)</summary>

###
[`v5.6.0`](https://redirect.github.com/actions/setup-python/compare/v5.5.0...v5.6.0)

[Compare
Source](https://redirect.github.com/actions/setup-python/compare/v5.5.0...v5.6.0)

</details>

---

### Configuration

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Automerge - At any time (no schedule defined).

🚦 **Automerge**: Enabled.

♻ **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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.github/workflows/auto-testing.yml

@@ -27,7 +27,7 @@ jobs:
       with:
         submodules: true
     - name: Set up Python ${{ matrix.python-version }}
-      uses: actions/setup-python@8d9ed9ac5c53483de85588cdf95a591a75ab9f55 # v5.5.0
+      uses: actions/setup-python@a26af69be951a213d495a4c3e4e4022e16d87065 # v5.6.0
       with:
         python-version: ${{ matrix.python-version }}
     - name: Install dependencies
@@ -62,7 +62,7 @@ jobs:
         with:
           submodules: true
       - name: Set up Python ${{ matrix.python-version }}
-        uses: actions/setup-python@8d9ed9ac5c53483de85588cdf95a591a75ab9f55 # v5.5.0
+        uses: actions/setup-python@a26af69be951a213d495a4c3e4e4022e16d87065 # v5.6.0
         with:
           python-version: ${{ matrix.python-version }}
       - name: Install dependencies & lib

.github/workflows/publish-to-pypi.yml

@@ -22,7 +22,7 @@ jobs:
       with:
         submodules: true
     - name: Set up Python
-      uses: actions/setup-python@8d9ed9ac5c53483de85588cdf95a591a75ab9f55 # v5.5.0
+      uses: actions/setup-python@a26af69be951a213d495a4c3e4e4022e16d87065 # v5.6.0
       with:
         python-version: '3.x'
     - name: Install dependencies