Update actions/upload-artifact action to v4

Author: renovate[bot]

.github/workflows/ruby.yml

@@ -68,7 +68,7 @@ jobs:
       - name: Save coverage
         run: ./cc-test-reporter format-coverage --output coverage/codeclimate.${{ matrix.ruby }}.json
 
-      - uses: actions/upload-artifact@v3.1.3
+      - uses: actions/upload-artifact@v4.0.0
         with:
           name: coverage-${{ matrix.ruby }}
           path: coverage/codeclimate.${{ matrix.ruby }}.json