eslint-plugin-react-hooks version: 4.2.0

## Steps To Reproduce

I know it shouldn't exist in production code, but it's annoying while editing some files.

```js
import React, { useEffect } from "react";

const App = () => {
  useEffect(); // <-
  return null;
};

export default App;
```

Link to code example: https://codesandbox.io/s/polished-sun-3wr27?file=/src/App.js

## The current behavior

ESLint crashed.

```
TypeError: Cannot read property 'type' of undefined
```

## The expected behavior

ESLint doesn't crash but reports an error instead.
switch (node.type) {
    case 'ObjectExpression':
      return 'object';
    case 'ArrayExpression':
      return 'array';
    case 'ArrowFunctionExpression':
    case 'FunctionExpression':
      return 'function';
    case 'ClassExpression':
      return 'class';
    case 'ConditionalExpression':
      if (
        getConstructionExpressionType(node.consequent) != null ||
        getConstructionExpressionType(node.alternate) != null
      ) {
        return 'conditional';
      }
      return null;
    case 'LogicalExpression':
      if (