Upgraded Github Action's upload artifact

Author: henryx

.github/workflows/gradle.yml

@@ -59,7 +59,7 @@ jobs:
             --info
         env:
           VAULT_VERSION: ${{ matrix.vault }}
-      - uses: actions/upload-artifact@v3  # upload test results
+      - uses: actions/upload-artifact@v4  # upload test results
         if: success() || failure()        # run this step even if previous step failed
         with:
           name: test-results