chore(deps): bump actions/setup-python from 5 to 6

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
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

.github/workflows/ci.yml

@@ -15,7 +15,7 @@ jobs:
     steps:
     - uses: actions/checkout@v5
     - name: Set up Python ${{ matrix.python-version }}
-      uses: actions/setup-python@v5
+      uses: actions/setup-python@v6
       with:
         python-version: ${{ matrix.python-version }}
         architecture: x64

.github/workflows/create_credentials_requirements_pr.yml

@@ -28,7 +28,7 @@ jobs:
           RELEASE_TAG=${GITHUB_REF#refs/tags/}
           sed -i -e "s|credentials-themes.git@.*|credentials-themes.git@$RELEASE_TAG#egg=edx_credentials_themes==$RELEASE_TAG|" requirements/base.in
 
-      - uses: actions/setup-python@v5
+      - uses: actions/setup-python@v6
         with:
           python-version: "3.12"
           architecture: x64