Remove outdated SearchModal test that expected hidden Dialog to remain in DOM

Removed test that checked for hidden Dialog still being in DOM.
The new behavior properly unmounts the Dialog when hidden, so
this test is now covered by the new unmounting tests.

Signed-off-by: fcamgz <fatihcamgoz@hotmail.com.tr>

plugins/search/src/components/SearchModal/SearchModal.test.tsx

@@ -151,22 +151,6 @@ describe('SearchModal', () => {
     expect(toggleModal).toHaveBeenCalledTimes(1);
   });
 
-  it('should render SearchModal hiding its content', async () => {
-    const { getByTestId } = await renderInTestApp(
-      <ApiProvider apis={apiRegistry}>
-        <SearchModal open hidden toggleModal={toggleModal} />
-      </ApiProvider>,
-      {
-        mountedRoutes: {
-          '/search': rootRouteRef,
-        },
-      },
-    );
-
-    expect(getByTestId('search-bar-next')).toBeInTheDocument();
-    expect(getByTestId('search-bar-next')).not.toBeVisible();
-  });
-
   it('should focus on its search bar when opened', async () => {
     await renderInTestApp(
       <ApiProvider apis={apiRegistry}>