Flaky RuleEngine test on CI: `ReferenceError: window is not defined`

[gciotola]

Describe the bug

CI randomly fails with an unhandled rejection while running
src/ui/forms/RuleEngine/index.test.tsx. Re-running the job usually makes it
pass.

https://github.com/commercelayer/app-elements/actions/runs/30795961354/job/91630433426

Unhandled Rejection
ReferenceError: window is not defined
 ❯ resolveUpdatePriority react-dom-client.development.js:1308:7
 ❯ dispatchSetState react-dom-client.development.js:9126:14
 ❯ src/ui/forms/RuleEngine/RuleEngineComponent.tsx:101:9

This error originated in "src/ui/forms/RuleEngine/index.test.tsx".
This error was caught after test environment was torn down.

Cause

RuleEngine calls fetchJsonSchema in an effect, which performs a real
network request to https://core.commercelayer.io/api/public/schemas/order_rules:
there is no MSW handler for it, and the URL is explicitly excluded from the
onUnhandledRequest warning in src/mocks/setup.ts. Depending on network
latency the promise can resolve after the test file has finished, so
setOptionsConfig runs against an already torn-down jsdom environment.

Expected

Tests must not depend on network timing. The schema request should be mocked,
and the component should not update state after unmount.