FIX eslint error

package.json

@@ -46,7 +46,7 @@
     "build": "react-scripts build",
     "test": "react-scripts test --env=jsdom --verbose",
     "eject": "react-scripts eject",
-    "test:coverage": "react-scripts test --env=jsdom --coverage && cat ./coverage/lcov.info | ./node_modules/coveralls/bin/coveralls.js",
+    "test:coverage": "react-scripts test --env=jsdom --coverage && cat ./coverage/lcov.info | coveralls",
     "lint": "(eslint --ext=js --ext=jsx . ) && echo Lint Passed! ALL Clear! ❤"
   },
   "devDependencies": {

src/components/__test__/Header.test.jsx

@@ -0,0 +1,34 @@
+import { shallow } from 'enzyme';
+import React from 'react';
+import Header from '../Header';
+
+describe('<Header /> Component', () => {
+  it('should show Sign In Button', () => {
+    const onClick = jest.fn();
+
+    const wrapper = shallow(<Header isSignIn={false} onClick={onClick} />);
+
+    const btn = wrapper.find('button');
+
+    expect(btn.text()).toBe('Sign In');
+
+    btn.simulate('click', 'text');
+
+    expect(onClick.mock.calls[0][0]).toBe('text');
+    expect(onClick).toHaveBeenCalledTimes(1);
+  });
+  it('should show Sign Out Button', () => {
+    const onClick = jest.fn();
+
+    const wrapper = shallow(<Header isSignIn onClick={onClick} />);
+
+    const btn = wrapper.find('button');
+
+    expect(btn.text()).toBe('Sign Out');
+
+    btn.simulate('click', 'text');
+
+    expect(onClick.mock.calls[0][0]).toBe('text');
+  });
+});
+

src/containers/__test__/Header.test.jsx

@@ -1,8 +1,14 @@
 import React from 'react';
 import { shallow } from 'enzyme';
 import Header from '../../components/Header';
+import HeaderContainer from '../Header';
 
 describe('Header Container Component', () => {
+  it('should render', () => {
+    const wrapper = shallow(<HeaderContainer />);
+    expect(wrapper.length).toBe(1);
+  });
+
   it('should show Sign In Button', () => {
     const onClick = jest.fn();