build(deps): 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] <support@github.com>

Author: dependabot[bot]

.github/workflows/gh-pages.yml

@@ -60,7 +60,7 @@ jobs:
     needs: [build]
     steps:
       - name: Download artifacts
-        uses: actions/download-artifact@v5
+        uses: actions/download-artifact@v6
         with:
           name: site
           path: site

.github/workflows/release-linux.yml

@@ -74,7 +74,7 @@ jobs:
       - uses: actions/setup-python@v6
         with:
           python-version: ${{ matrix.python-version }}
-      - uses: actions/download-artifact@v5
+      - uses: actions/download-artifact@v6
         with:
           pattern: dist-*
           merge-multiple: true
@@ -119,7 +119,7 @@ jobs:
       - uses: actions/setup-python@v6
         with:
           python-version: "3.12"
-      - uses: actions/download-artifact@v5
+      - uses: actions/download-artifact@v6
         with:
           pattern: dist-*
           merge-multiple: true

.github/workflows/release-osx-win.yml

@@ -99,7 +99,7 @@ jobs:
       - uses: actions/setup-python@v6
         with:
           python-version: "3.12"
-      - uses: actions/download-artifact@v5
+      - uses: actions/download-artifact@v6
         with:
           pattern: dist-*
           merge-multiple: true