prohibit `&&` conditional rendering in the return statement of a component

```jsx
// avoid
const WrapTingy = ({ cond }) => (
  cond && <Tingy/>
);
 
// that would error if cond is `undefined`, use this version instead:
 
const WrapTingy = ({ cond }) => (
  <>{cond && <Tingy/>}</>
);
```