chore(deps): bump actions/upload-artifact in the actions-deps group

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


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

---
updated-dependencies:
- dependency-name: actions/upload-artifact
  dependency-version: '6'
  dependency-type: direct:production
  update-type: version-update:semver-major
  dependency-group: actions-deps
...

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

Author: dependabot[bot]

.github/workflows/deploy-prod.yml

@@ -34,7 +34,7 @@ jobs:
 
       - run: mvn --batch-mode -P prod,!local -Drevision=${{ steps.get_version.outputs.version }} install
 
-      - uses: actions/upload-artifact@v5
+      - uses: actions/upload-artifact@v6
         with:
           name: ${{ env.ARTIFACT_NAME }}
           path: target/Learnweb.war

.github/workflows/deploy.yml

@@ -30,7 +30,7 @@ jobs:
 
       - run: mvn --batch-mode -P prod,!local -Dmaven.test.skip=true -Drevision=dev-${{ github.sha }} install
 
-      - uses: actions/upload-artifact@v5
+      - uses: actions/upload-artifact@v6
         with:
           name: ${{ env.ARTIFACT_NAME }}
           path: target/Learnweb.war