Bump actions/upload-artifact from 4 to 6

Bumps [actions/upload-artifact](https://github.com/actions/upload-artifact) from 4 to 6.
- [Release notes](https://github.com/actions/upload-artifact/releases)
- [Commits](actions/upload-artifact@v4...v6)

---
updated-dependencies:
- dependency-name: actions/upload-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/action-test.yml

@@ -45,7 +45,7 @@ jobs:
           testsfilter: checkstyle,test4tests
       - name: Artifact output
         if: ${{ always() }}
-        uses: actions/upload-artifact@v4
+        uses: actions/upload-artifact@v6
         with:
           name: apacheyetustestpatchactionout
           path: ${{ github.workspace }}/out

.github/workflows/yetus.yml

@@ -61,7 +61,7 @@ jobs:
           --tests-filter=checkstyle,javadoc,rubocop,test4tests
       - name: Artifact output
         if: ${{ always() }}
-        uses: actions/upload-artifact@v4
+        uses: actions/upload-artifact@v6
         with:
           name: apacheyetuspatchdir
           path: ${{ github.workspace }}/out