Build(deps): Bump actions/upload-artifact from 5 to 6 (#36686)

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)

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

.github/workflows/release-notes.yml

@@ -75,7 +75,7 @@ jobs:
           bin/rake "release_note:plugins:generate[ ${{ steps.dates.outputs.from }} , ${{ steps.dates.outputs.to }} , ./tmp/all-the-plugins/official/* , discourse ]" | tee tmp/notes/plugins.txt
 
       - name: Export files
-        uses: actions/upload-artifact@v5
+        uses: actions/upload-artifact@v6
         with:
           name: release-notes
           path: ./tmp/notes/*.txt

.github/workflows/tests.yml

@@ -291,7 +291,7 @@ jobs:
         if: matrix.build_type == 'frontend' && matrix.target == 'themes'
         run: DISCOURSE_DEV_DB=discourse_test bin/rake themes:qunit_all_official
 
-      - uses: actions/upload-artifact@v5
+      - uses: actions/upload-artifact@v6
         if: always() && matrix.build_type == 'frontend'
         with:
           name: ember-exam-execution-${{ matrix.target }}-${{ matrix.browser }}-frontend-${{ hashFiles('./frontend/discourse/test-execution-*.json') }}
@@ -345,7 +345,7 @@ jobs:
         shell: bash
 
       - name: Upload failed system test artifacts
-        uses: actions/upload-artifact@v5
+        uses: actions/upload-artifact@v6
         if: always() && steps.check-failed-system-test-artifacts.outputs.exists == 'true'
         with:
           name: failed-system-test-artifacts-${{ matrix.build_type }}-${{ matrix.target }}
@@ -377,7 +377,7 @@ jobs:
         run: cp tmp/turbo_rspec_flaky_tests.json tmp/turbo_rspec_flaky_tests-${{ matrix.build_type }}-${{ matrix.target }}-${{ steps.fetch-job-id.outputs.job_id }}.json
 
       - name: Upload flaky tests report
-        uses: actions/upload-artifact@v5
+        uses: actions/upload-artifact@v6
         if: steps.check-flaky-spec-report.outputs.exists == 'true'
         with:
           name: flaky-test-reports-${{ matrix.build_type }}-${{ matrix.target }}
@@ -389,7 +389,7 @@ jobs:
     needs: build
     steps:
       - name: Merge Artifacts
-        uses: actions/upload-artifact/merge@v5
+        uses: actions/upload-artifact/merge@v6
         with:
           name: failed-system-test-artifacts
           pattern: failed-system-test-artifacts-*
@@ -399,7 +399,7 @@ jobs:
         continue-on-error: true
 
       - name: Merge Artifacts
-        uses: actions/upload-artifact/merge@v5
+        uses: actions/upload-artifact/merge@v6
         with:
           name: flaky-test-reports
           pattern: flaky-test-reports-*