add missing jest import to setup file

Author: kligarski

versioned_docs/version-7.x/testing.md

@@ -34,6 +34,8 @@ import { setUpTests } from 'react-native-reanimated';
 setUpTests();
 
 // Silence the warning: Animated: `useNativeDriver` is not supported because the native animated module is missing
+import { jest } from '@jest/globals';
+
 jest.mock('react-native/Libraries/Animated/NativeAnimatedHelper');
 ```