Bump the actions group across 1 directory with 3 updates (#7751)

Bumps the actions group with 3 updates in the / directory: [actions/setup-python](https://github.com/actions/setup-python), [actions/setup-node](https://github.com/actions/setup-node) and [prefix-dev/setup-pixi](https://github.com/prefix-dev/setup-pixi).


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

Updates `actions/setup-node` from 4 to 6
- [Release notes](https://github.com/actions/setup-node/releases)
- [Commits](https://github.com/actions/setup-node/compare/v4...v6)

Updates `prefix-dev/setup-pixi` from 0.9.0 to 0.9.2
- [Release notes](https://github.com/prefix-dev/setup-pixi/releases)
- [Commits](https://github.com/prefix-dev/setup-pixi/compare/v0.9.0...v0.9.2)

---
updated-dependencies:
- dependency-name: actions/setup-python
  dependency-version: '6'
  dependency-type: direct:production
  update-type: version-update:semver-major
  dependency-group: actions
- dependency-name: actions/setup-node
  dependency-version: '6'
  dependency-type: direct:production
  update-type: version-update:semver-major
  dependency-group: actions
- dependency-name: prefix-dev/setup-pixi
  dependency-version: 0.9.2
  dependency-type: direct:production
  update-type: version-update:semver-patch
  dependency-group: actions
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: Jeremy Tuloup <jeremy.tuloup@gmail.com>

.github/workflows/build.yml

@@ -138,7 +138,7 @@ jobs:
             py_cmd: python
     steps:
       - name: Install Python
-        uses: actions/setup-python@v5
+        uses: actions/setup-python@v6
         with:
           python-version: ${{ matrix.python }}
           allow-prereleases: true

.github/workflows/buildutils.yml

@@ -72,7 +72,7 @@ jobs:
         uses: actions/checkout@v5
 
       - name: Install Python
-        uses: actions/setup-python@v5
+        uses: actions/setup-python@v6
         with:
           python-version: '3.10'
           architecture: 'x64'

.github/workflows/upgrade-jupyterlab-dependencies.yml

@@ -40,12 +40,12 @@ jobs:
           ref: ${{ inputs.branch || 'main' }}
 
       - name: Set up Python
-        uses: actions/setup-python@v5
+        uses: actions/setup-python@v6
         with:
           python-version: '3.11'
 
       - name: Install Node
-        uses: actions/setup-node@v4
+        uses: actions/setup-node@v6
         with:
           node-version: '20.x'
 
@@ -79,7 +79,7 @@ jobs:
             jlpm
             jlpm deduplicate
           fi
-      - uses: prefix-dev/setup-pixi@v0.9.0
+      - uses: prefix-dev/setup-pixi@v0.9.2
         with:
           pixi-version: v0.41.4
           manifest-path: pyproject.toml