fix: typo in cheatsheet.mdx (#1196)

Typo in cheatsheet.mdx

Author: tiborbarsi

docs/dom-testing-library/cheatsheet.mdx

@@ -151,7 +151,7 @@ test('loads items eventually', async () => {
   fireEvent.click(getByText(node, 'Load'))
 
   // Wait for page to update with query text
-  const items = await findByText(node, /Item #[0-9]: /)
+  const items = await findAllByText(node, /Item #[0-9]: /)
   expect(items).toHaveLength(10)
 })
 ```