Update GitHub Artifact Actions to v4

Author: renovate[bot]

.github/workflows/ruby.yml

@@ -75,7 +75,7 @@ jobs:
       - name: Save coverage
         run: ./cc-test-reporter format-coverage --output coverage/codeclimate.${{ matrix.ruby }}.json
 
-      - uses: actions/upload-artifact@v3.1.2
+      - uses: actions/upload-artifact@v4.3.1
         with:
           name: coverage-${{ matrix.ruby }}
           path: coverage/codeclimate.${{ matrix.ruby }}.json
@@ -96,12 +96,12 @@ jobs:
       - name: Give test coverage reporter executable permissions
         run: chmod +x cc-test-reporter
 
-      - uses: actions/download-artifact@v3.0.2
+      - uses: actions/download-artifact@v4.1.2
         with:
           name: coverage-2.6
           path: coverage
 
-      - uses: actions/download-artifact@v3.0.2
+      - uses: actions/download-artifact@v4.1.2
         with:
           name: coverage-2.7
           path: coverage