Bump actions/download-artifact from 5 to 6

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

---
updated-dependencies:
- dependency-name: actions/download-artifact
  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/python-tests.yml

@@ -96,7 +96,7 @@ jobs:
           git config --system gpg.program "C:\Program Files (x86)\gnupg\bin\gpg.exe"
         if: runner.os == 'Windows'
       - run: uv sync --group test --group docs --extra rich
-      - uses: actions/download-artifact@v5
+      - uses: actions/download-artifact@v6
         with:
           name: Packages
           path: dist
@@ -118,7 +118,7 @@ jobs:
       id-token: write
     needs: [test]
     steps:
-    - uses: actions/download-artifact@v5
+    - uses: actions/download-artifact@v6
       with:
         name: Packages
         path: dist
@@ -132,7 +132,7 @@ jobs:
     permissions:
       contents: write
     steps:
-    - uses: actions/download-artifact@v5
+    - uses: actions/download-artifact@v6
       with:
         name: Packages
         path: dist
@@ -149,7 +149,7 @@ jobs:
     permissions:
       id-token: write
     steps:
-    - uses: actions/download-artifact@v5
+    - uses: actions/download-artifact@v6
       with:
         name: Packages
         path: dist