feat: Added Theme and migrate to emotion@10.x 🚀 (#286)

* chore: updated emotion dependency

* feat: introduced theme

* refactor: updated emotion styles

* fix: fixed emotion error

* fix: fixed tests

* chore: add missing types

Co-Authored-By: Thomas Klein <tmkn@users.noreply.github.com>

src/utils/test-react-testing-library.tsx

@@ -0,0 +1,12 @@
+import { render } from '@testing-library/react';
+import React from 'react';
+
+import ThemeProvider from '../design-tokens/ThemeProvider';
+
+/* eslint-disable @typescript-eslint/explicit-function-return-type */
+const customRender = (node: React.ReactElement<any>, ...options: Array<any>) => {
+  return render(<ThemeProvider>{node}</ThemeProvider>, ...options);
+};
+
+export * from '@testing-library/react';
+export { customRender as render };