build(deps): bump prefix-dev/setup-pixi from 0.8.3 to 0.8.4

Bumps [prefix-dev/setup-pixi](https://github.com/prefix-dev/setup-pixi) from 0.8.3 to 0.8.4.
- [Release notes](https://github.com/prefix-dev/setup-pixi/releases)
- [Commits](prefix-dev/setup-pixi@v0.8.3...v0.8.4)

---
updated-dependencies:
- dependency-name: prefix-dev/setup-pixi
  dependency-version: 0.8.4
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

Author: dependabot[bot]

.github/workflows/macos-linux-windows-pixi.yml

@@ -93,7 +93,7 @@ jobs:
           key: ccache-macos-linux-conda-${{ matrix.os }}-${{ matrix.build_type }}-${{ matrix.environment }}_${{ github.sha }}
           restore-keys: ccache-macos-linux-conda-${{ matrix.os }}-${{ matrix.build_type }}-${{ matrix.environment }}_
 
-      - uses: prefix-dev/[email protected].3
+      - uses: prefix-dev/[email protected].4
         with:
           cache: true
           environments: ${{ matrix.environment }}

.github/workflows/update_pixi_lockfile.yml

@@ -27,7 +27,7 @@ jobs:
           persist-credentials: false
 
       - name: Set up pixi
-        uses: prefix-dev/[email protected].3
+        uses: prefix-dev/[email protected].4
         with:
           run-install: false