Chore: add footnote component

test/components/common/Footnote.spec.js

@@ -0,0 +1,19 @@
+import React from 'react'
+import { render } from '@testing-library/react-native'
+
+import Footnote from '../../../components/common/Footnote'
+
+describe('Footnote component', () => {
+  test('when children are present, renders them', () => {
+    const text = 'Some footnote text'
+    const { toJSON } = render(<Footnote>{text}</Footnote>)
+
+    expect(toJSON()).toMatchSnapshot()
+  })
+
+  test('when no children, renders nothing', () => {
+    const { toJSON } = render(<Footnote></Footnote>)
+
+    expect(toJSON()).toMatchSnapshot()
+  })
+})