[ResponseOps][Cases] Fix flaky title tests (elastic#190048)

Fixes elastic#187364

## Summary

Updated the tests to stop using enzyme.

x-pack/plugins/cases/public/components/case_form_fields/title.test.tsx

@@ -7,18 +7,21 @@
 
 import type { FC, PropsWithChildren } from 'react';
 import React from 'react';
-import { mount } from 'enzyme';
-import { act } from '@testing-library/react';
+import { screen } from '@testing-library/react';
 
 import type { FormHook } from '@kbn/es-ui-shared-plugin/static/forms/hook_form_lib';
+import type { CaseFormFieldsSchemaProps } from './schema';
+
 import { useForm, Form } from '@kbn/es-ui-shared-plugin/static/forms/hook_form_lib';
+import userEvent from '@testing-library/user-event';
+
 import { Title } from './title';
 import { schema } from '../create/schema';
-import type { CaseFormFieldsSchemaProps } from './schema';
+import { createAppMockRenderer, type AppMockRenderer } from '../../common/mock';
 
-// FLAKY: https://github.com/elastic/kibana/issues/187364
-describe.skip('Title', () => {
+describe('Title', () => {
   let globalForm: FormHook;
+  let appMockRender: AppMockRenderer;
 
   const MockHookWrapperComponent: FC<PropsWithChildren<unknown>> = ({ children }) => {
     const { form } = useForm<CaseFormFieldsSchemaProps>({
@@ -35,42 +38,37 @@ describe.skip('Title', () => {
 
   beforeEach(() => {
     jest.resetAllMocks();
+    appMockRender = createAppMockRenderer();
   });
 
   it('it renders', async () => {
-    const wrapper = mount(
+    appMockRender.render(
       <MockHookWrapperComponent>
         <Title isLoading={false} />
       </MockHookWrapperComponent>
     );
 
-    expect(wrapper.find(`[data-test-subj="caseTitle"]`).exists()).toBeTruthy();
+    expect(await screen.findByTestId('caseTitle')).toBeInTheDocument();
   });
 
   it('it disables the input when loading', async () => {
-    const wrapper = mount(
+    appMockRender.render(
       <MockHookWrapperComponent>
         <Title isLoading={true} />
       </MockHookWrapperComponent>
     );
-
-    expect(wrapper.find(`[data-test-subj="caseTitle"] input`).prop('disabled')).toBeTruthy();
+    expect(await screen.findByTestId('input')).toBeDisabled();
   });
 
   it('it changes the title', async () => {
-    const wrapper = mount(
+    appMockRender.render(
       <MockHookWrapperComponent>
         <Title isLoading={false} />
       </MockHookWrapperComponent>
     );
 
-    await act(async () => {
-      wrapper
-        .find(`[data-test-subj="caseTitle"] input`)
-        .first()
-        .simulate('change', { target: { value: 'My new title' } });
-    });
+    userEvent.paste(await screen.findByTestId('input'), ' is updated');
 
-    expect(globalForm.getFormData()).toEqual({ title: 'My new title' });
+    expect(globalForm.getFormData()).toEqual({ title: 'My title is updated' });
   });
 });