CI: Bump actions/upload-artifact from 5 to 6

Bumps [actions/upload-artifact](https://github.com/actions/upload-artifact) from 5 to 6.
- [Release notes](https://github.com/actions/upload-artifact/releases)
- [Commits](https://github.com/actions/upload-artifact/compare/v5...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>

.github/workflows/js-and-wasm-artifacts.yml

@@ -163,14 +163,14 @@ jobs:
           fi
 
       - name: Upload js package
-        uses: actions/upload-artifact@v5
+        uses: actions/upload-artifact@v6
         with:
           name: ladybird-js-${{ matrix.package_type }}
           path: Build/distribution/ladybird-js-*.tar.gz
           retention-days: 7
 
       - name: Upload wasm package
-        uses: actions/upload-artifact@v5
+        uses: actions/upload-artifact@v6
         with:
           name: ladybird-wasm-${{ matrix.package_type }}
           path: Build/distribution/ladybird-wasm-*.tar.gz

.github/workflows/js-and-wasm-benchmarks.yml

@@ -115,7 +115,7 @@ jobs:
           ./run.py ${run_options}
 
       - name: 'Save results as an artifact'
-        uses: actions/upload-artifact@v5
+        uses: actions/upload-artifact@v6
         with:
           name: js-benchmarks-results-${{ matrix.os_name }}-${{ matrix.arch }}
           path: js-benchmarks/results.json

.github/workflows/lagom-template.yml

@@ -211,7 +211,7 @@ jobs:
 
       - name: Upload LibWeb Test Artifacts
         if: ${{ always() && inputs.build_preset != 'Fuzzers' && inputs.build_preset != 'All_Debug' }}
-        uses: actions/upload-artifact@v5
+        uses: actions/upload-artifact@v6
         with:
           name: libweb-test-artifacts-${{ inputs.os_name }}-${{ inputs.build_preset }}-${{ inputs.toolchain }}-${{ inputs.clang-plugins }}
           path: ${{ github.workspace }}/Build/Lagom/Tests/LibWeb/test-web/test-dumps/