Bump actions/download-artifact from 5 to 6 (#2680)

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

Author: dependabot[bot]

.github/workflows/release.yaml

@@ -249,7 +249,7 @@ jobs:
             type=semver,pattern={{version}},value=${{ env.VERSION }}
 
       - name: Download digests
-        uses: actions/download-artifact@v5
+        uses: actions/download-artifact@v6
         with:
           path: /tmp/digests
           pattern: digests-operator-*
@@ -303,7 +303,7 @@ jobs:
             type=semver,pattern={{version}},value=${{ env.VERSION }}
 
       - name: Download digests
-        uses: actions/download-artifact@v5
+        uses: actions/download-artifact@v6
         with:
           path: /tmp/digests
           pattern: digests-kubectl-*