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.
break;
            case 'inlineReducer':
              extraWarning =
                ` If '${setStateRecommendation.setter}' needs the ` +
                `current value of '${setStateRecommendation.missingDep}', ` +
                `you can also switch to useReducer instead of useState and ` +
                `read '${setStateRecommendation.missingDep}' in the reducer.`;
              break;
            case 'updater':
              extraWarning =
                ` You can also do a functional update '${
                  setStateRecommendation.setter
                }(${setStateRecommendation.missingDep.substring(
                  0,
                  1,
                )} => ...)' if you only need '${
                  setStateRecommendation.missingDep
                }'` + ` in the '${setStateRecommendation.setter}' call.`;
              break;
            default:
              throw new Error('Unknown case.');
          }
        }
      }
      reportProblem({
        node: declaredDependenciesNode,
        message:
          `React Hook ${context.getSource(reactiveHook)} has ` +
          
          (getWarningMessage(missingDependencies, 'a', 'missing', 'include') ||