Wait for composite to initialize in unit tests

packages/block-editor/src/components/color-palette/test/control.js

@@ -1,7 +1,7 @@
 /**
  * External dependencies
  */
-import { render } from '@testing-library/react';
+import { render, waitFor, queryByAttribute } from '@testing-library/react';
 
 /**
  * Internal dependencies
@@ -10,9 +10,22 @@ import ColorPaletteControl from '../control';
 
 const noop = () => {};
 
+async function renderAndValidate( ...renderArgs ) {
+	const view = render( ...renderArgs );
+	await waitFor( () => {
+		const activeButton = queryByAttribute(
+			'data-active-item',
+			view.baseElement,
+			'true'
+		);
+		expect( activeButton ).not.toBeNull();
+	} );
+	return view;
+}
+
 describe( 'ColorPaletteControl', () => {
 	it( 'matches the snapshot', async () => {
-		const { container } = render(
+		const { container } = await renderAndValidate(
 			<ColorPaletteControl
 				label="Test Color"
 				value="#f00"