Bump actions/setup-python from 5 to 6 (#135)

Bumps [actions/setup-python](https://github.com/actions/setup-python) from 5 to 6.
- [Release notes](https://github.com/actions/setup-python/releases)
- [Commits](actions/setup-python@v5...v6)

---
updated-dependencies:
- dependency-name: actions/setup-python
  dependency-version: '6'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

.github/workflows/check.yml

@@ -19,7 +19,7 @@ jobs:
         uses: actions/checkout@v5
 
       - name: Set up Python 3.x
-        uses: actions/setup-python@v5
+        uses: actions/setup-python@v6
         with:
           python-version: '3.x'
 

.github/workflows/docs.yml

@@ -34,7 +34,7 @@ jobs:
           fetch-depth: 0
 
       - name: Set up Python 3.x
-        uses: actions/setup-python@v5
+        uses: actions/setup-python@v6
         with:
           python-version: '3.x'
 

.github/workflows/pypi-publish.yml

@@ -15,7 +15,7 @@ jobs:
     - uses: actions/checkout@v5
 
     - name: Set up Python
-      uses: actions/setup-python@v5
+      uses: actions/setup-python@v6
       with:
         python-version: '3.x'
 

.github/workflows/tests.yml

@@ -39,7 +39,7 @@ jobs:
           fetch-depth: 0
 
       - name: Set up Python ${{ matrix.python-version }}
-        uses: actions/setup-python@v5
+        uses: actions/setup-python@v6
         with:
           python-version: ${{ matrix.python-version }}