ci: bump actions/download-artifact from 4 to 5 in the actions group

Bumps the actions group with 1 update: [actions/download-artifact](https://github.com/actions/download-artifact).


Updates `actions/download-artifact` from 4 to 5
- [Release notes](https://github.com/actions/download-artifact/releases)
- [Commits](actions/download-artifact@v4...v5)

---
updated-dependencies:
- dependency-name: actions/download-artifact
  dependency-version: '5'
  dependency-type: direct:production
  update-type: version-update:semver-major
  dependency-group: actions
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

.github/workflows/publish.yml

@@ -110,7 +110,7 @@ jobs:
       SONATYPE_AUTH: "Authorization: Bearer ${{secrets.SONATYPE_TOKEN}}"
     steps:
       - name: Download artifacts
-        uses: actions/download-artifact@v4
+        uses: actions/download-artifact@v5
         with:
           path: kbigint
           pattern: kbigint-*