chore(deps): bump prefix-dev/setup-pixi in the actions group (sustainability-software-lab#102)

Bumps the actions group with 1 update: [prefix-dev/setup-pixi](https://github.com/prefix-dev/setup-pixi).


Updates `prefix-dev/setup-pixi` from 0.9.3 to 0.9.4
- [Release notes](https://github.com/prefix-dev/setup-pixi/releases)
- [Commits](prefix-dev/setup-pixi@v0.9.3...v0.9.4)

---
updated-dependencies:
- dependency-name: prefix-dev/setup-pixi
  dependency-version: 0.9.4
  dependency-type: direct:production
  update-type: version-update:semver-patch
  dependency-group: actions
...

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

Author: dependabot[bot]

.github/workflows/ci.yml

@@ -33,7 +33,7 @@ jobs:
           fetch-depth: 0
 
       - name: Set up pixi
-        uses: prefix-dev/setup-pixi@v0.9.3
+        uses: prefix-dev/setup-pixi@v0.9.4
         with:
           pixi-version: v0.59.0
           environments: ${{ matrix.python-version }}

.github/workflows/copilot-setup-steps.yml

@@ -29,7 +29,7 @@ jobs:
         uses: actions/checkout@v6
 
       - name: Set up pixi
-        uses: prefix-dev/setup-pixi@v0.9.3
+        uses: prefix-dev/setup-pixi@v0.9.4
         with:
           pixi-version: v0.56.0
           cache: false # No caching